81 


..  LIBRARY 

^  OF   THE 

UNIVERSITY  OF  CALIFORNIA. 


GIFT    OF 


Received 


r 

Shelf  No. 


RETURN     BIOLOGY  LIBRARY 

rO^*^-     3503  Life  Sciences  Bldg.     642-2531 


6GRAPH 


ALL  BOOKS  MAY  BE  RECALLED  AFTER  7  DAYS 
Renewed  books  are  subject  to  immediate  recall 

>PEAS  STAMPED  BELOW 


; 


ED 


APR 


FORM  NO.  DD4 


UNIVERSITY  OF  CALIFORNIA,  BERKELEY 
BERKELEY,  CA  94720 

®s 


CALIFORNIA    STATE    SERIES    OF    SCHOOL    TEXT-BOOKS. 


ANATOMY 
PHYSIOLOGY 
HYGIENE 


COMPILED     UNDER    THE     DIRECTION 
or  THE 

STATE    BOARD  OF    EDUCATION. 


SACRAMENTO,    CALIFORNIA. 
PRINTED    AT    THE    STATE    PRINTING    OFFICE. 


BIOLOGY 

LIBRARY 

G 


Entered  according  to  Act  of  Congress  in  the  year  1891 , 
By  Henry  H.  Markham,  James  W,  Anderson,  Ira  More,  Charles  W.  Childs,  and 

Edward  T.  Pierce, 

STATE     BOARD     OF     EDUCATION 

Of  the  State  of  California,  for  the  People  of  the  State  of  California. 


PREFACE. 


The  objects  kept  in  view  in  the  preparation  of  this 
book  have  been: 

To  teach  the  organs  and  functions  of  the  human  body. 
To  show  how  health  may  be  kept. 
To  develop  powers  of  observation. 
To  teach  the  use  of  pictures. 

The  facts  of  Anatomy  and  Physiology  are  put  as  sim- 
ply and  clearly  as  possible;  something  in  the  way  of 
object  lessons,  with  the  child  himself  as  an  object.  The 
pupil  is  encouraged  to  look  in  the  fields  and  markets  to 
see  the  truth  of  the  statements  made,  and  is  constantly 
referred  to  the  pictures  that  illustrate  the  text  for  a  bet- 
ter understanding.  Common  diseases  are  mentioned,  and 
the  habits  that  lead  to  them  emphasized. 

The  book  is  in  two  parts,  because  it  seems  wiser  to 
learn  the  parts  and  uses  of  a  machine  before  attempting 
to  run  it,  and  the  dependence  of  the  systems  is  so  inti- 
mate that  a  knowledge  of  all  should  precede  an  attempt 
to  study  the  hygiene  of  any  one. 

The  second  part,  Hygiene,  serves  as  a  comprehensive 
review  of  Anatomy  and  Physiology.  The  subjects  are 
arranged  as  they  are,  because  the  child  can  thus  proceed 
in  the  scientific  way  from  the  known  to  the  unknown. 
The  parts  of  the  body,  the  supporters  (bones),  the 
movers  (muscles),  and  the  cover  (skin),  are  easily  recog- 
nized from  the  outside  of  the  body.  The  reason  of 
motion,  of  growth,  of  flow  of  blood  when  a  finger  is  cut,. 


PREFACE. 

must  be  found  inside  the  body  in  the  vital  organs:  the 
organs  of  respiration,  digestion,  and  circulation.  The 
ruler  of  all  these  organs  is  found  in  the  nervous  system, 
which,  being  more  intricate  than  any  other,  should  be 
studied  last,  when  the  child  has  become  familiar  with 
physiological  study. 

The  scientific  names  connected  with  the  illustrations 
and  in  the  glossary  are  for  the  use  of  teachers  and  older 
pupils;  English  names  have  been  inserted,  as  far  as  pos- 
sible, for  the  use  of  the  younger  pupils. 

It  is  not  claimed  that  the  subject  is  exhausted.  Two 
things  have  been  kept  in  mind:  that  the  mental  capacity 
of  children  is  limited,  and  that  " cramming"  should  be 
avoided.  Therefore  a  number  of  interesting  and  impor- 
tant facts  have  been  left  for  the  study  of  later  years. 
Experienced  teachers  will  have  no  trouble  in  selecting 
supplemental  material  for  teaching,  and  inexperienced 
teachers  may  find  it  helpful  to  supplement  from  any  of 
the  authors  mentioned  in  the  list  of  good  works  on 
anatomy  and  physiology.  Teachers  will  find  Martin's 
Human  Body,  Briefer  Course,  excellent  in  suggestions  for 
object  work. 

All  the  cuts  illustrating  the  text,  except  otherwise 
marked,  were  made  especially  for  this  book  by  Sarah  P. 
Monks. 

In  the  critical  revision  of  the  proof  sheets  the  Board 
of  Education  has  been  fortunate  in  having  the  assistance 
of  Miss  Lucy  M.  Washburn,  teacher  of  Physiology  in 
the  State  Normal  School  at  San  Jose;  Mrs.  Julia  B. 
Hoitt,  Deputy  Superintendent  of  Public  Instruction; 
Dr.  J.  W.  Hunt,  Los  Angeles,  California;  Dr.  A.  C.  Avery, 
San  Jose,  California;  Mr.  C.  F.  Holder,  author  of  an 
Elementary  Zoology  and  editor  of  the  Los  Angeles  Trib- 
une, Los  Angeles,  California;  Prof.  M.  L.  Seymour,  teacher 


PREFACE. 


of  Physiology  in  the  State  Normal  School  at  Chico,  Cali- 
fornia; Mrs.  Ellen  H.  Richards,  Institute  of  Technology, 
Boston,  Mass.;  and  Prof.  E.  D.  Cope,  University  of  Penn- 
sylvania, Philadelphia,  Pa. 


TABLE     OF     CONTENTS. 


I. 

PAGE. 

CHAPTER     1 — The  Human  Body 7 

CHAPTER    2— The  Bones '    .  20 

CHAPTER    3 — The  Muscles 36 

CHAPTER    4  —The  Skin  and  its  Appendages 48 

CHAPTER    5 — The  Food  System       62 

CHAPTER    6— The  Circulation 83 

CHAPTER    7 — The  Breathing  Organs 103 

CHAPTER    8 — The  Nervous  System 112 

CHAPTER    9 — The  Special  Senses     .     .   % 127 

PART  II. 

CHAPTER    1 — General  Hygiene 151 

CHAPTER    2 — Hygiene  of  the  Bones 153 

CHAPTER    3 — Hygiene  of  the  Muscles 156 

CHAPTER    4 — Hygiene  of  the  Skin        161 

CHAPTER    5 — Hygiene  of  the  Alimentary  Canal 167 

CHAPTER    6— Alcohol  and  Narcotics 186 

CHAPTER    7 — Hygiene  of  the  Organs  of  Circulation    ....  202 

CHAPTER    8— Care  of  the  Breathing  Organs 208 

CHAPTER    9 — Care  of  the  Organs  of  the  Special  Senses       .     .  222 

CHAPTER  10 — Care  of  the  Nervous  System 225 

GLOSSARY 246 

MISCELLANEOUS  FACTS 260 

INDEX 261 

GYMNASTICS  . 273 


I. 
ANATOMY    AND     PHYSIOLOGY. 


CHAPTER    1. 

THE    HUMAN   BODY. 

The  human  body  may  be  divided  into  three  parts — the 
head,  trunk,  and  limbs. 

The  Head. — The  head  has  two  important  parts — the 
head  proper  and  the  face.  By  rubbing  the  hand  over  the 
head  it  will  be  found  that  the  outside  substance  moves 
easily,  and  that  under  it  is  something  hard.  On  the  fore- 
head the  loose  part  can  be  pinched  up.  It  is  the  skin, 
with  a  little  flesh. 

If  the  top  of  the  head  were  cut  off,  the  head  part  would 
be  seen  as  a  hollow,  irregular  box  of  bone,  and  it  is  this 
box  that  we  feel  when  the  hand  is  pressed  on  the  head. 
This  roundish  box  with  its  hard  bone  walls  is  a  strong 
protection  to  the  soft  brain,  which  is  inside.  Bone  can 
be  felt  by  rubbing  the  hand  anywhere  over  the  face. 

At  the  cheeks  the  flesh  between  the  bone  and  the  skin 
is  thicker  than  elsewhere  on  the  face,  and  so  soft  that 
quite  a  lump  can  be  pinched  up  between  the  thumb  and 
finger.  The  flesh  is  called  muscle.  In  animals  that  we 
eat,  the  flesh,  as  mutton  and  beef,  is  called  lean  meat. 

When  the  cheeks  are  pinched  they  get  red,  and  the 
lips  of  people  in  health  are  always  red.  This  means  that 
there  are  many  little  tubes  in  muscle  that  are  filled  with 
blood.  When  a  person  cuts  or  scratches  his  hand,  the 
tubes  are  opened,  and  the  blood  flows  out,  and  thus  it  is 
seen  to  be  red.  On  the  backs  of  the  hands,  at  the  wrists 
and  temples,  we  can  see  these  blood  vessels  standing  up 
like  bluish  cords. 


PHYSIOLOGY. 


14 


THE  HUMAN  BODY. 


When  you  take  hold  of  your  ear  or  nose,  another  sub- 
stance is  found  which  is  not  so  hard  as  bone  nor  so  soft 
as  skin  and  muscle.  It  bends  easily.  It  is  cartilage,  or 
gristle.  It  is  the  hard,  white,  shiny  substance  that  is  seen 
at  the  end  of  meat  bones. 

These — skin,  bone,  muscle,  blood  vessels,  cartilage — 
are  substances  that  form  the  head,  and  are  found,  also, 
in  other  parts  of  the  body. 

The  large,  hollow  place  that  holds  the  brain  is  called 
the  cranial  cavity.  There  are  a  number  of  other  smaller 
hollows  in  the  skull  which  hold  very  important  organs 
(Fig.  1).  Your  eyes  look  out  of  two  little  caves  under 

f  1.  Brain  (Cranial}  Cavity. 
2.  Eye  (Orbital)  Cavity  (2). 
Head  Cavities.  •{  3.  Ear  (Aural)  Cavity  (2). 

4.  Nose  (Nasal)  Cavity  (divided). 
[  5.  Mouth  (Oral)  Cavity. 


FIG.  1(  Copied).— 
Human  Body. 


Trunk  Cavities. 


Extremities. 


Upper,  or  Arm. 


f  6.  Chest  ( Thoracic)  Cavity. 

7.  Bowel  (Abdominal  and  Pelvic) 
Cavity. 

8.  Shoulder. 

9.  Arm. 

15.  Forearm. 
Wrist. 
Hand. 
Fingers. 
f  10.  Hip. 

11.  Thigh. 
I  Lower,  or  Leg.  <j  12.  Knee. 

13.  Leg. 
1 14.  A»kle. 
'  * 

fc 


10  PHYSIOLOGY. 

the  forehead.  You  can  feel  a  ring  of  bone  all  around  the 
front  part.  This  hollow  is  called  the  orbital,  or  eye  cavity. 
On  each  side  of  the  head  there  is  a  small  opening,  sur- 
rounded by  the  ear  cartilage,  which  leads  away  into  the 
ear  cavity,  where  the  wonderful  organs  of  hearing  are 
hidden.  The  lips  shut  up  the  mouth  cavity.  The  carti- 
lage, skin,  and  muscles  of  the  nose  cover  the  cavity  where 
the  organs  of  smell  are  found. 

The  Trunk. — The  trunk  is  usually  called  the  body,  and 
it  differs  a  good  deal  from  the  head.  Hold  your  hands 
tightly  against  the  lower  part  of  your  waist  a  few  minutes, 
and  you  will  feel  motion.  What  is  it  made  by?  Press 
against  different  parts  of  the  trunk,  and  breathe.  The 
upper  part  moves,  but  has  hard  walls,  not  as  solid  as 
those  of  the  head,  though  very  much  more  solid  than 
those  of  the  lower  part  of  the  trunk.  Lower  down  the 
trunk  is  extremely  soft,  except  at  the  back  and  hips.  It 
is  as  soft  as  the  cheeks.  At  the  back  of  the  trunk  there 
is  a  number  of  small,  irregular-shaped  bones  which  extend 
the  whole  length  of  the  back,  and  are  joined  together, 
one  above  the  other,  by  little  bands.  They  form  what 
is  called  the  backbone. 

At  the  upper  part  of  the  trunk  there  are  many  curved 
bones,  called  ribs.  They  start  at  the  backbone  and  curve 
around  something  like  the  hoops  of  a  barrel,  to  join  the 
breast  bone  in  front.  Their  curved  shape  can  be  traced 
by  the  fingers.  They  move  up  and  down  when  we 
breathe.  They  are  the  bones  that  make  the  upper  portion 
of  the  trunk  more  rigid  than  the  lower.  Find  out  how 
far  down  they  extend.  The  upper  cavity  of  the  trunk  is 
called  the  chest  cavity,  and  the  lower  the  cavity  of  the 
abdomen. 

The  Limbs. — The  limbs,  or  extremities,  are  the  legs 
and  arms.  The  arm  is  divided  into  arm,  forearm,  wrist, 


THE  HUMAN  BODY. 


11 


hand,  and  fingers.  The  leg,  into  thigh,  leg,  ankle,  foot,  and 
toes  ( Fig.  1 ) .  The  limbs  are  unlike  the  head  and  trunk, 
although  made  of  much  the  same  substances.  A  thumb 
may  be  taken  as  an  example  of  the  arrangement  of  the 
parts  of  the  limbs.  It  can  be  bent,  and  moved  easily 
backward  and  forward,  showing  that  it  is  made  of  a 
number  of  bones.  The  place  where  the  bones  join  is 
called  &  joint. 

Joints  make  it  possible  to  bend  fingers  and  toes,  arms 
and  legs.  Inside  the  thumb  the  hard  bone  can  be  felt, 
then  the  soft  muscle,  and  over  all  the  elastic  skin.  The 
nails  at  the  ends  of  the  fingers  and  toes  can  be  bent,  but 
they  are  not  as  flexible  as  gristle.  The  arrangement  of 
bone,  muscle,  and  skin  can  be  seen  in  the  leg  bones  of  beef 
and  mutton  at  the  market. 


EPIDERMIS 


FIG.  2.  Section  of  Thumb. 


Fig.  2  shows  the  inside  of  a  thumb  cut 
lengthwise.  The  bones  are  long,  hollow  inside,  and 
porous  at  the  ends.  There  is  something  fastened  to 
the  bone  that  looks  like  cord.  It  is  tendon.  It  tapers 
down  from  the  large  muscle  and  fastens  it  to  the 
bones.  Similar  tendons  can  be  felt  and  seen  inside 
the  wrist,  and  they  are  the  hard  cords  found  at  the 
small  end  of  a  chicken's  "drumstick."  The  bulky  part 
on  the  inside  of  the  hand,  at  the  base  of  the  thumb,  is 
muscle,  and  looks  fibrous.  The  mottled  appearance 


12  PHYSIOLOGY. 

just  under  the  skin  in  the  figure  shows  fat.     Over  all  is 
seen  the  skin. 

Even  an  examination  of  the  outside  shows  that  the 
body  is  made  of  many  substances.  We  can  see  hair, 
skin,  and  nails;  just  under  the  skin  in  many  places  ten- 
dons and  blood  vessels  are  easily  found;  and  cartilage 
and  bones  may  be  felt,  and  their  shapes  traced  by  external 
examination.  These  make  the  body,  as  bricks,  mortar, 
and  wood  make  a  house.  They  are  called  tissues. 

Tissues. — A  tissue  is  any  solid  substance  that  forms 
part  of  the  body.  Tissues  differ  very  much.  Some,  like 
bone,  are  hard;  some  are  tough,  like  cartilage;  some  are 
soft,  like  flesh;  some  are  elastic,  like  skin;  and  each  one 
has  work  to  do. 

Fluids. — The  moisture  of  the  mouth,  and  the  blood  in 
the  veins,  are  examples  of  fluids  of  the  body.  In  all  the 
tissues  and  fluids  there  is  a  large  amount  of  water.  Even 
the  bones  are  part  water. 

Cells. — Under  the  microscope  something  new  is  seen. 
This  instrument,  which  makes  things  that  are  invisible 
to  the  unaided  eye  large  enough  to  be  seen,  shows  of 
what  the  tissues  are  made.  They  are  built  of  cells.  Most 
fluids  of  the  body  also  contain  cells.  The  cells  are  very 
small,  and  of  different  shapes.  Fig.  3  shows  various 
cells.  They  are  exceedingly  numerous,  and  even  though 
so  small,  most  of  them  are  very  important  portions -of 
the  human  system. 

Organs. — A  number  of  tissues  and  fluids  together 
form  an  organ.  An  organ  is  a  part  of  the  body  that  has 
a  particular  work  to  do.  and  this  work  is  called  the  use 
or  function  of  the  organ.  The  tissues — skin,  flesh,  bone, 
tendon,  and  blood  vessels — form  the  hand,  which  is  an 
organ  for  grasping;  various  fluids  and  tissues  form  the 


THE  HUMAN  BODY. 


13 


FIG.  3.  Cells.— 1.  Nerve  Cells  (multipolar);  2.  Blood  Cells,  or  Cor- 
puscles ;  3.  Liver,  or  Hepatic  Cells ;  4.  Fat  Cells ;  5.  Striped  Muscles 
(with  bead-like  cells);  6.  Unstriped  muscles  (spindle-shaped  cells). 

eye,  which  is  an  organ  for  seeing;  the  lungs,  that  cause  the 
chest  walls  to  rise  and  fall  when  the  air  is  drawn  in  and 
forced  out,  are  organs  of  breathing;  and  the  heart,  which 
you  can  feel  thumping  against  your  left  side,  is  an  organ 
to  drive  the  blood  through  the  blood  vessels.  ' 

The  heart  is  a  single  organ.  Many  of  our  organs  are  in 
pairs.  There  are  two  eyes,  two  ears,  two  arms,  two  legs, 
and  two  lungs.  Even  the  heart  is  divided  into  two  parts, 
and  the  nasal  cavity  has  a  partition,  which  makes  two 
nostrils.  But  some  other  organs,  like  mouth  and  stom- 
ach, are  not  divided,  or  in  pairs. 

Systems. — A  number  of  organs  working  together 
make  a  system.  The  heart,  blood  vessels,  and  blood  form 
the  blood  circulating  system.  The  teeth,  tongue,  and  the 
stomach,  which  aches  when  wrong  material  or  bad  food 
is  eaten,  and  some  other  organs,  make  the  food  or  digestive 


14 


PHYSIOLOGY. 


FIG.  4  (Copied).  Absorbent  System. — S.  Superficial  vessels;  Z>.  Deep- 
seated  vessels;  1.  Thoracic  Duct;  2.  Chyle  receptacle  (Receptaculum 
chylii);  3.  Lacteals. 

system.     The  system  that  takes  in  poison  when  one  is 
injured  by  poison  oak,  is  called  the  absorbent  system. 

The  systems  are  closely  connected,  and  are  dependent 
upon  one  another.  When  all  organs  and  systems  work 
well  a  person  is  not  conscious  of  his  body,  and  is  said  to 
be  in  good  health.  If  one  organ  gets  out  of  order,  other 
parts  are  apt  to  be  affected,  and  the  whole  body  becomes 
uncomfortable  or  c£is-eased. 


THE  HUMAN  BODY.  15 

Anatomy. — Anatomy  tells  how  tissues  and  organs  are 
made,  where  the  organs  are,  and  describes  their  shape, 
color,  and  general  appearance. 

Physiology. — Physiology  teaches  the  function,  use,  or 
working  of  organs  and  parts  of  the  body. 

Hygiene. — School  children  do  not  study  text-books  of 
physiology  merely  to  learn  the  description  and  functions 
of  organs,  but  to  learn  what  it  is  right  to  eat  and  drink, 
how  to  avoid  poisonous  and  injurious  things,  and  how  to 
live  and  work  and  think  so  as  to  have  strong,  well  bodies 
that  can  do  their  work  comfortably  and  perfectly.  It  is 
easier  to  keep  from  getting  sick  than  to  get  well  when 
health  is  broken  down.  Hygiene  is  the  science  that 
teaches  the  laws  of  health. 


TOPICAL    SUMMARY. 

Write  what  you  remember  of  Chapter  1  under  the  fol- 
lowing heads: 

Head.  Limbs. 

Parts.  Names. 

Tissues.  partgt 

Fluids.  Joints. 

Cavities.  Tendons. 

Systems. 


Tissues. 
Backbone.  ~  ,, 

Ribs.  Cells- 

Parts. 

Upper.  Anatomy. 

Lower. 

Front.  Physiology, 

Back. 

Cavities.  Hygiene. 


16  PHYSIOLOGY. 

QUESTIONS. — Which  of  the  following  statements  relate 
io  anatomy,  which  to  physiology,  and  which  to  hygiene? 

Skin  is  in  two  layers. 

Liver  is  made  of  angular  cells. 

The  heart  propels  blood. 

Blood  is  part  water. 

Tobacco  injures  the  nervous  system. 

Unstriped  muscle  is  made  of  spindle-shaped  cells. 

Perspiration  keeps  the  body  cool. 

Reading  fine  print  at  dusk  injures  the  eyesight. 

Saliva  helps  dissolve  food. 

Organs  are  made  of  tissue. 

Alcoholic  drinks  injure  the  brain. 

Make  three  original  statements  relating  to  anatomy. 
Three  relating  to  physiology.     Three  relating  to  hygiene. 

Questions  to  be  answered  from  memory  will  be  found 
at  the  end  of  Part  I. 


THE  SKELETON. 


17 


Head  Bones. 
29. 


Total,  206. 


Trunk  Bones. 
57. 


Bones  of  Ex- 
tremities .  . 
120. 


f    1.  Frontal  (1). 

2.  Parietal  (2). 

3.  Temple,  or  Temporal  (2). 

4.  Occipital  (1). 

5.  Cheek  (Malar}  (2). 

6.  Nose  (Nasal}  (2). 
6a.  Vomer  (1). 

7.  Lower  Jaw  (Inferior  Maxillary}  (1). 

8.  Upper  Jaw  (Superior  Maxillary}  (2). 

Not  shown  in  figure :  Sphenoid  (1),  Ethmoid  (1), 
Turbinated  (2),  Lachrymal  (2),  Palate  (2),  Ear 
bones  (6),  Tongue  (Hyoid}  bone  (1). 

9.  Collar  bone  (Clavicle}  (2). 

9a.  Shoulder  blade  (Scapula}  (2). 
10.  Ribs  (24). 
10a.  Breast  bone  (Sternum)  (1). 

a.  N  eck  ( Cervical)  Ver- 

tebrae (7). 

b.  Back  (Dorsal)  Ver- 

tebrae (12). 

c.  Loin  (Lumbar)  Ver- 

tebrae (5). 

d.  Hip     (Sacral),   five 

consolidated  (1). 

e.  Coccyx  or  Coccyg- 

eal,    consolidated 
(1),  or  imperfect. 
[  12.  Hip  (Innominata)  Bones  (2). 

13.  Humerus(2). 

14.  Radius  (2). 

15.  Ulna  (2). 

16.  Wrist  bones  (Carpals)  (16). 

17.  Metacarpals  (10). 

18.  Finger  bones  (Phalanges)  (28). 


11.  Spinal  (Vertebral)  Column.  <| 


Arm. 
60. 


19.  Thigh  bone  (Femur)  (2). 

20.  Kneepan  (Patella)  (2). 

21.  Tibia  (2).. 

22.  Fibula  (2). 

23.  Ankle  bones  (Tarsals)  (14). 

24.  Instep  (Metatarsals)  (10). 

25.  Toe  bones  (Phalanges)  (28). 
26.  Ligaments 


Leg. 
60. 


(Authors  differ,  because  some  count  the  teeth,  making  238 ;  some  do 
not  count  ear  bones;  some  do  not  count  patellae.) 
2— P 


18 


PHYSIOLOGY. 


13 


THE  SKELETON. 


19 


26- 


20 


PHYSIOLOGY. 


CHAPTER   2. 

BONES. 

The  Skeleton. — By  simply  pressing  on  different  parts 
of  the  body  it  is  found  that  there  is  a  bony  framework 
beneath  the  skin  and  flesh,  but  this  examination  does 
not  give  a  satisfactory  idea  of  the  form  or  the  number  of* 
bones.  It  is  easy  to  count  the  separate  pieces  that  make 
the  fingers  and  the  hand,  but,  from  the  outside,  no  one 
could  tell  how  many  bones  there  are  in  the  ankle,  or  the 
wrist,  and  would  suppose  that  the  skull  is  but  a  single 
curved  bone.  Fig.  5  shows  how  the  bones  of  the  body  look 
when  the  soft  tissues  are  removed.  These  bones  make 
what  is  called  the  skeleton.  It  takes  about  two  hundred 
bones  to  form  the  skeleton,  and  they  are  of  very  differ- 
ent shapes  and  sizes  (Figs.  5,  6). 

FIG.  7.  Cranium. — 1.  Mas- 
toid  Process  of  Temporal 
Bone;   2.   Styloid  Pro- 
cess. 

Flat   Bones. — 

Most  of  the 
head  bones 
are  curved, 
and  all  of 
them  are  flat 
and  rather 
thin  (Fig. 
7).  They 
are  called 
flat  bones. 
The  shoul- 
der blade 

(Fig.  8)  is  an  excellent  example  of  a  flat  bone.     The  hip 

bones  (Figs.  5,  6)  also  belong  to  this  class. 


ASAL 


BONES. 


21 


Long  Bones. — Look  at  the  thigh  bone  (Figs.  9,  5,  6), 

FIG.  8.  Shoulder  Blade  (Scapula).— 1.  Shoulder 
Socket ;  2.  Openings  for  blood  vessels  and  nerves. 


FIG.  9.  Back  of 
Thigh  Bone  (Right 
Femur). — 1, 1.  Open- 
ings for  blood  ves- 
sels and  veins. 


and  you  will  find 
another  class  of 
bones.  In  the  hands 
and  feet,  arms  and 
legs,  most  of  the 
bones  are  long  and 

roundish,  something  like  rods  (Figs.  10,  5, 
6).     They  are  called  long  bones.     They  are 
widened  at  the  ends,  and  in  some  of  them  the 
ends  are  very  much  rounded.     The  two 
tremities  of  long  bones  are  called  heads,  and 
the  part  between  is  the  shaft.     The  femur 
(Fig.  9)  is  the  longest  bone  of  the  body, 
and  its  upper  end  is  so  round  that  there 
is  good  reason  for  calling  it  a  head. 

Irregular  Bones. — The  backbone, 
or  spinal  column  (Fig.  11),  shows 
another  class.  The  pieces  that  form  it 
have  very  peculiar  shapes.  They  be- 
long to  the  third  class,  called  irregular 


22 


PHYSIOLOGY. 


FIG.  10  (Copied}.  I.  Hand.— Ph.  Finger  Bones  (Phalanges);  Me. 
Bones  of  the  hand  between  wrist  and  lingers  (Metacarpals) ;  A.  A.  A. 
(T.  Ligaments,  T.  Trapezium,  T.  Trapezoid,  M.  Magnum,  U.  Unci- 
form,  £  Scaphoid,  S.  Semi-lunar,  C.  Cuneiform,  P.  Pisiform,  Wrist, 
or  Carpal,  Bones,  or  Carpalia. 

II.  Finger  Bone  without  Ligaments. — M.  Metacarpal. 


Those  of  the  wrist  and  of  the  ankle  are  also  of 
this  class. 

Processes. — All  bones  have  projections,  called  pro- 
cesses and  ridges,  for  attachment  of  muscles,  and  in 
many  places  the  bones  are  made  rough  by  the  pulling  of 
tendons.  In  muscular  people  the  bones  are  rougher,  and 
the  processes  and  ridges  larger,  than  in  others,  because 
their  muscles  are  more  developed  and  pull  on  the  bone 
harder. 


BONES. 


7.  Neck  (Cervical)  Vertebrae. 


23 


co       7 


-a  | 


t 


12.  Back  (Dorsal)  Vertebrae. 


11 


12 


5.  Loin  (Lumbar)  Vertebrae. 


Hip  (Sacral)  Vertebrae  (5.  Consolidated). 


Coccygeal  Vertebrae  (3  or  4,  imperfect). 


24 


PHYSIOLOGY. 


On  the  skull  (Fig.  7),  just  back  of  the  ear,  there  is  a 
stout  process,  called  the  mastoid  process,  which  you  can 
find  on  your  own  head.  The  muscle  fastened  to  it  and 
passing  down  the  side  of  the  neck  can  be  pinched  up 
between  the  thumb  and  fingers,  if  the  head  is  held  side- 
wise.  There  is  another  process  of  the  temporal  bone  seen 
in  Fig.  7,  that  looks  like  a  thick  needle. 

The  projections  along  the  spinal  column  are  stout  pro- 
cesses, called  spines  or  spinous  processes  (Fig.  11),  and 
the  ridge  of  the  shoulder  blade,  also  called  a  spine  (Fig. 
8),  is  a  good  example  of  a  ridge  for  muscular  attachment. 

Openings  in  Bone. — On  the  surface  of  any  dried  bone 
you  pick  up  you  can  see  a  great  number  of  little  openings 
like  pin  holes.  They  are  shown  in  Figs.  9,  8.  They 
are  in  all  bones.  They  are  openings  through  which  the 
blood  vessels  enter,  for  bone,  like  all  parts  of  the  body,  is 
alive,  and  needs  blood  to  bring  it  material  to  keep  it  strong 
and  well. 

Color. — When  inside  the  body,  bone  does  not  look  like 
the  bleached  pieces  sometimes  picked  up  on  the  street  or 
in  the  field.  If  it  is  exposed  to  the  weather  it  becomes 
white;  if  buried,  it  gets  stained  a  blackish  or  brownish 
color,  from  the  soil;  but  when  it  is  fresh,  bone  is  of  a 
delicate  pinkish  color. 

Cover. — Bones  have  a  kind  of  coat  over  them.  It  is 
thin,  pinkish,  and  fits  closely;  but  in  meat  bones  it  can 
be  pulled  off,  like  a  skin,  from  the  harder  part.  It  nour- 
ishes them,  and  helps  mend  them  when  they  are  broken. 
It  is  called  bone  cover  (periosteum). 

Structure. — Next  to  the  outside  cover  the  bones  are 
hard  and  dense.  After  that  there  is  a  porous  layer,  and 
then  another  dense  layer,  which  can  be  seen  in  any 
broken  piece.  This  is  all  there  is  of  the  flat  bones. 

If  you  break  open  a  chicken's  leg,  you  will  find  a  long 


BONES.  25 

hollow  inside  the  last  dense  layer.  In  soup  bones,  and 
in  the  long  bones  of  dogs  and  sheep,  and  other  domestic 
animals,  the  hollow  is  filled  with  a 
yellowish,  fatty  substance.  It  is  called 
-HEAD  the  marrow.  Do  not  look  for  marrow 
in  the  chicken's  bone;  the  long  bones 
of  birds  are  hollow.  This  makes  them 
light  and  enables  them  to  fly  easily. 
JsHArT  The  ends  of  the  long  bones  are 

quite  porous,  the  fibres  of  bone  form- 
ing there  a  kind  of  network.  This 
can  be  seen  in  a  bone  cut  lengthwise 
(Fig.  12),  or  by  breaking  any  long 
bone  you  may  find. 
FIG.  12.  section  of  Microscopic  Structure.— The 

Humerus.  .  . 

microscopic  structure  of  bone  is  very 

interesting,  for  it  shows  how  it  is  possible  for  the  blood 
to  circulate  all  through  so  hard  a  substance  as  bone. 

Connected  with  the  small  holes  that  can  be  seen  on  the 
outside  of  any  bone,  there  are  minute  canals,  invisible  to 
the  unaided  eye,  which  run  in  different  directions,  and 
branch  like  the  roots  of  trees.  Little  crooked  tubes  run 
from  them,  and  lead  to  irregular  lake-like  spaces. 

I.,  Fig.  13,  shows  two  of  the  canals,  and  their  branches, 
cut  lengthwise.  II.,  Fig.  13,  shows  one  cut  across,  with 
the  tiny  lakes,  like  long  black  spots,  and  the  fine  thread- 
like tubes  connecting  the  lakes  with  the  canals.  The 
blood  comes  in  through  the  small  holes  in  the  outside, 
enters  the  canals,  goes  through  the  crooked  tubes,  comes 
to  the  lakes,  and  there  nourishes  all  the  surrounding 
particles  of  bone. 

Composition. — In  Chapter  1  it  was  said  that  even 
bone  is  made  partly  of  water.  It  is  easy  to  guess,  from 
its  hardness,  that  it  must  have  also  something  in  it  that 


26 


PHYSIOLOGY. 


I. 


II. 


FIG.  13.  Bone  Sections.— I.  Vertical  Section:  1,  1.  Haversian  Canal; 
2.  Little  Lakes  (Lacunas);  3.  Little  Canals  (Canaliculi). 
II.  Cross  Section :  1.  Haversian  Canal ;  2.  Lacuna ;  3.  Canaliculi. 

is  like  stone.  It  has.  This  is  a  mineral,  made  of  the 
same  materials  as  the  marble  which  is  used  for  making 
statues,  and  for  trimming  brick  or  stone  houses.  It  is 
called  limestone,  or  carbonate  of  lime.  Bone,  however,  is 
composed  of  limestone  and  another  mineral  called  phos- 
phate of  lime. 

Experiments. — But  if  there  were  only  water  and  this 
kind  of  lime  in  the  bone,  it  would  look  like  the  marble 
of  statues  and  gravestones,  but  it  does  not.  Water  and 
lime  make  up  only  two  thirds  of  the  bone.  What  is  the 
rest?  Something  you  never  would  guess  by  merely  look- 
ing at  the  bone.  It  is  animal  matter,  not  very  unlike 
cartilage.  This  can  easily  be  shown  by  soaking  a  bone, 
like  those  from  mutton  chops,  or  a  chicken's  leg,  for  a 
day  in  dilute  muriatic  acid.  All  the  mineral  will  be 
taken  out,  and  the  animal  part  that  remains  will  be  so 
tough  and  flexible  that  it  can  be  tied  in  a  knot,  if  it  is 
long  enough.  To  get  rid  of  the  animal  matter  in  a  bone, 
put  it  into  the  fire.  All  the  water  and  animal  part 
burns  away,  and  the  lime  remains  white  and  brittle  and 
porous. 


BONES.  27 

In  both  experiments  the  bone  keeps  its  shape  and  size, 
but  it  loses  weight.  They  show  the  use  of  each  material, 
and  how  closely  they  are  connected.  The  lime  makes  it 
hard  and  strong,  and  the  animal  portion  makes  it  tough 
and  flexible.  By  comparing  some  bone  that  has  been  in 
the  street  a  long  time  with  one  fresh  from  the  market,  it 
will  be  seen  that  exposure  to  weather  also  drives  out  part 
of  the  animal  matter. 

Proportion  of  Mineral  and  Animal  Matter. — The 
ratio  of  the  two  substances  in  bone  varies  with  age  and 
individuals.  In  the  bones  of  babies  there  is  a  great  deal 
more  of  animal  matter  than  of  mineral;  in  young  chil- 
dren there  is  more  than  in  grown  people,  and  in  old  people 
there  is  very  much  more  mineral  than  animal  matter. 
That  is  the  reason  children's  bones  bend  easily,  and  are 
not  so  apt  to  break  from  slight  falls. 

The  habit  of  letting  babies  stand  too  early  bends  the 
soft  bones  of  the  legs,  and  makes  them  what  is  called 
bow-legged.  The  extra  lime  in  the  bones  of  old  persons 
makes  them  so  brittle  that  they  break  readily.  There  is 
also  a  great  difference  in  persons  of  the  same  age  in 
regard  to  the  two  materials.  Sometimes  a  fall  from  a 
chair  will  result  in  the  breaking  of  a  bone  in  one  child, 
while  in  another  child  it  only  bruises  the  flesh. 

Broken  Bone. — When  a  bone  is  broken,  if  the  two 
edges  are  held  firmly  together  for  some  time  it  will  knit, 
or  grow  together  again,  and  be  as  strong  as  ever.  At  first 
the  joined  part  is  flexible^but  after  a  few  weeks  it  hard- 
ens like  the  old  part.  This  is  because  the  blood  has 
taken  to  it  all  the  lime  it  needed.  In  fact,  so  much 
mineral  has  been  taken  there  that,  a  ridge  is  made,  which 
is  only  smoothed  down  after  a  number  of  years  have 
passed,  by  the  blood  carrying  away  by  degrees  the  excess 
of  material. 


28 


PHYSIOLOGY. 


Joints. — Bones  are  joined  together  in  different  ways, 
according  to  their  uses  and  the  amount  of  motion  required. 
By  opening  and  shutting  the  hand,  it  is  seen  that  the 
bones  double  up  on  each  other  very  readily  in  closing, 
but  there  is  only  a  limited  motion 
backward.  The  same  is  true  of 
toes,  elbows,  and  knees.  Because 
they  move  something  like  hinges, 
they  are  called  hinge  joints.  These 
hinges  are  swinging  all  day  long, 
and  still  they  never  creak.  The 
hinges  of  a  door  often  creak,  and 
some  one  is  only  too  glad  to  apply 
oil  to  stop  the  noise.  The  hinge 
joints  are  also  oiled.  There  is  a 
membrane  at  each  joint  that  man- 
ufactures a  smooth,  whitish  fluid, 
something  like  the  white  of  egg, 
called  synovia,  that  comes  between 
the  two  rubbing  surfaces  and 
makes  them  move  smoothly. 

The  hinge  joints  (Fig.  14)  are 
very  wonderful.     First,  there  are 

FIG.  14  (Copied).  Section  the  wide  ends  of  the  two  bones, 
ofKneeJomt.—l.  Knee  pan  .  ,  , 

(Patella};  2.  Mass  of  Fat;  3.  and  over  each  there  is  a  hard,  pol- 

ished  cap  of-cartilage  that,  in  beef 

6.  Thigh  bone  (Femur).  bones,  can  be  cut,  and  that  looks 
something  like  dull  glass.  Then  comes  the  thin  mem- 
brane which  makes  the  oiling 'material.  Then  all  these 
are  bound  together  by  straps  of  ligaments  (Fig.  10),  or 
cap-like  ligaments  (Fig.  15). 

The  ligament  is  inelastic,  white,  and  fibrous,  and  it  is 
everywhere  found  binding  bones  together  when  joints 
have  any  motion. 

Not  all  joints  are  hinge  joints.     Stiffen  your  arm  and 


BONES.  29 

swing  it  around.     See  how 
many     motions     you     can 
make — up,  down,  backward, 
forward,    and    around  in  a 
circle.     A  hinge  joint  can- 
not do  that.     Try   twisting    1- 
your  finger  around  in  that  way. 
At  a  meat  market  can  be  seen  how  a 
calf's,    sheep's,  or  cow's  hind   leg 
joins  the  body. 

Fig.  15  shows  the  most  perfect  joint  of 
this  kind.  There  is  a  deep  socket  in 
one  bone  and  a  round  head  at  the  end 
of  the  other.  The  ball  fits  smoothly 
into  the  hollow.  It  is  called  a  ball  and 
socket  joint.  In  the  hip  joint  there 
is  a  small  ligament  which  fastens  the 
head  of  the  thigh  bone  to  ttie  inside 

of  the  socket  to  help  hold  it  in  place.  (Capsular) Ligament;  3. 
xx  ,  .  T  ,  i  .  TIT  L  Thigh  bone,  or  femur. 

Outside  there  is  a  cap-like  ligament 

extending  from  the  hip  bone  to  the  thigh  bone  (Figs. 
5,  6).  The  shoulder  is  nearly  as  good  an  example  of  ball 
and  socket  joint.  It  admits  of  a  great  deal  of  motion. 

Place  your  hands  on  your  spinal  column  and  bend 
backward  and  forward  and  from  side  to  side.  A  new 
joint  is  found.  The  parts  of  the  backbone  cannot  shut 
up  on  themselves  like  the  fingers,  nor  swing  as  freely  as 
the  arms.  The  motion  is  limited,  for  the  most  part,  to  a 
glide,  and  the  joints  are  called  plane  or  gliding  joints. 

All  the  joinings  of  bones  of  the  extremities  and  spinal 
column  admit  of  motion,  and  they  are  called  movable  joints. 
Nearly  all  the  head  bones  are  fastened  closely  together. 
In  most  of  them  the  bony  edges  are  jagged,  like  irregular 
saw  teeth,  and  they  fit  together  so  as  to  hold  the  bones  in 
place  without  ligaments  (Fig.  7).  These  joints  are 


30 


PHYSIOLOGY. 


called  sutures.  Sometimes,  as  between  the  temporal  and 
parietal  bones,  the  edges  merely  lap  over  (Fig.  7).  These 
and  the  sutures  are  immovable  joints. 

The  under  part  of  the  back  of  the  head  fits  on  the 
spinal  column.  Move  your  head  up  and  down,  and  from 
side  to  side;  it  acts  as  though  it  were  fastened  by  a  ball 
and  socket  joint.  There  is  something  like  one.  On  the 
under  side  of  the  skull  there  is  a  short,  curved  process, 
something  like  a  rocker,  on  each  side  of  the  opening, 
through  which  the  spinal  cord  passes.  These  fit  into 
long  hollows,  like  grooves,  on  the  first  vertebra  (Fig.  18, 
I.  3),  and  the  head  rocks  forward  and  back- 
ward, with  its  rockers  in  the  grooves. 


I. 


II. 


•piG.  16.— I.  Atlas :  1.  Ligament ;  2.  End  of  Odontoid  Process ;  3. 
Places  on  which  the  curved  processes  of  the  head  move;  4.  Opening 
for  nerves  and  blood  vessels. 

II.  Axis  (side  view):  A.  Odontoid  Process;  B.  Spinous  Process; 
C.  Opening  for  nerves  and  blood  vessels. 

It  cannot  twist  around  on  these.  The  second  vertebra 
has  a  peg-like  process  on  its  upper  side  (Fig.  16,  II.  A). 
This  peg  fits  into  a  hollowed-out  place  in  the  first  ver- 
tebra (Fig.  16,  I.),  and  is  held  in  its  place  by  a  ligament, 
and  when  we  turn  our  heads  the  first  vertebra  and  the 
head  move  on  the  pivot  of  the  second  vertebra.  This  is 
called  a  pivot  joint.  When  a  person's  neck  is  broken,  it 
is  generally  the  peg  that  breaks  through  the  ligament, 
and  kills  by  pressing  against  the  spinal  cord. 


BONES. 


31 


Shape  of  the  Skull. — The  skull,  or  brain  box,  is 
shown  in  Figs.  5,  6,  7,  and  its  shape  can  be  seen  and  felt 
on  any  head.  It  is  curved  like  a  dome,  and  this  is  the 
strongest  form  in  the  world  for  resisting  blows  or  press- 
ure. It  has  this  perfect  shape  in  order  to  protect  the 
delicate,  soft  brain.  The  sutures  add  to  its  protecting 
power.  If  it  were  solid,  and  a  blow  received  hard  enough 
to  fracture  the  bone,  the  break  would  extend  a  great  dis- 
tance. As  it  is,  when  a  skull  bone  is  broken,  the  break 
extends  only  to  the  suture,  which  scatters  or  distributes 
the  jar.  The  most  delicate  organs  of  the  body — the 
brain,  the  eye,  and  the  ear — are  thus  well  protected  by 
the  strong,  arched,  and  sutured  skull. 

The  Ribs. — The  internal  organs  of  the  trunk  are  par- 
tially protected  by  bones — the  ribs,  spinal  column,  and  hip 
bones  (Figs.  5,  6).  There  are  twenty-four  ribs.  They 
are  generally  fastened,  in  pairs,  to  the  breast  bone  by  car- 
tilage, and  to  the  spinal  column  by  ligaments,  and  they 
move  freely  up  and  down  when  we  breathe.  They  have 
the  strong,  arched  shape. 

By  looking  at  Figs.  5,  6,  it  will  be  seen  that  they 
are  not  all  joined  to  the  breast  bone  in  the  same  way. 
Seven  pairs  join  the  breast  bone  by  their  own  cartilage, 
and  are  called  true  ribs.  Three  pairs  are  fastened  to  the 
cartilage  of  the  seventh  rib,  and  are  called  false  ribs;  and 
two  pairs  are  free,  or  floating  ribs.  Fig.  17  shows  the 
relation  between  the  ribs  and  soft  organs  beneath,  the 
dotted  lines  showing  the  position  of  such  organs. 

Press  hard  with  both  hands  against  the  floating  ribs. 
You  will  perceive  how  easily  the  ribs  are  bent  in,  and 
how  it  is  possible  for  a  silly  girl  to  make  a  small  waist. 
The  five  lower  pairs  of  ribs  are  pressed  down  on  the  soft 
organs  inside  the  trunk.  Do  you  think  it  can  be  com- 
fortable? 


32 


PHYSIOLOGY. 


FIG.  17.  Torso— Showing  Ribs  and  relative  positions  of  vital  organs 
of  Trunk.  Dotted  lines  show  organs  which  are  beneath  Ribs  and 
Sternum. 

The  Hip  Bones  and  Spinal  Column.— The  hip 
bones  form  the  lower  part  of  the  pelvic  cavity,  and  are 
fastened  to  the  spinal  column  (Figs.  5,  6).  A  number 
of  vertebrae  in  the  lower  end  of  the  spinal  column  are 
joined  firmly  together,  and  thus  make  a  stronger  support 
for  the  hips  and  upper  part  of  the  trunk.  The  spinal 
column  (Fig.  11)  is  made  of  many  pieces,  called  verte- 
brae, that  vary  in  size  and  shape.  Nearly  every  separate 
bone  has  a  broad,  flat  part  in  front,  on  which  rests  a  pad 


BONES. 


33 


of  cartilage  when  the  bones  are  fastened  together,  a  spinous 
part  projecting  backward,  and  a  hole  through  which  the 
spinal  cord  passes  (Fig.  18).  The  spines  give  it  the 
name  of  spinal  column. 

This  column  is  sometimes  incor- 
rectly  called    the     backbone,    as 


FIG.  18.  Loin  (Lumbar)  Vertebra. — 
I.  Top  View:  1.  Opening  for  spinal 
cord. 

II.  Side:  1, 1.  Opening  for  spinal  cord. 

though  it  were  all  in  one  piece.  In  many  people  the 
spinous  processes  can  easily  be  felt  on  the  neck,  especially 
the  last,  or  seventh,  neck  vertebra.  In  very  thin  horses 
they  stand  up  all  along  the  back  like  knots.  Bones  are 
always  seen  when  the  padding  of  fat  is  wasted  away. 

Curves  and  Cartilage. — The  spinal  column  has 
several  curves.  These  serve  to  lessen  or  prevent  injury 
to  the  brain  in  case  of  a  fall.  The  cartilages  between  the 
vertebrae  also  serve  to  deaden  a  shock  or  jar.  During 
the  day,  while  one  is  on  one's  feet  a  great  deal,  the  pads 
of  cartilage  get  compressed  and  thin;  but  at  night,  by 
resting,  they  expand.  A  person  is  therefore  shorter  at 
night  than  he  is  in  the  morning. 


FOR  THE  TEACHER. 


Procure  several  fresh  bones  from  the  market  and  ask 

3— P 


34  PHYSIOLOGY. 

each  child  to  bring  any  bone  he  can  get.     Compare,  notice 
differences. 

Old  Bone.  Fresh  Bone. 

Dry.  Moist. 

Many  holes  outside.  No  holes. 

Whitish.  Pinkish    (with  spots   marking   tiny 

blood  vessels). 

No  periosteum.  Periosteum  (hard  to  pull  off). 

No  cartilage.  Shiny  cartilages  on  ends. 

No  ligaments.  Ligaments. 

Clean.  Having  shreds  of  muscle. 

Hollow.  Has  marrow  inside. 

Brittle.  Tough. 

Porous  inside.  Pores  filled  with  marrow  or  vessels. 

Points  in  Common. 

Ridges  arid  processes  for  attachment  of  tendons.  Koughness. 
Hardness.  Expanded  ends  and  shaft  (if  long  bone). 

Notice  processes  on  irregular  bones.  Notice  hollow  for 
spinal  cord  in  vertebrae.  In  bones  of  young  animals 
(calves,  lambs)  notice  the  ends.  Generally  they  separate 
easily  from  the  rest.  That  means  that  the  ends  ossify 
free  from  the  rest  and  join  afterwards  as  the  animal 
grows  older. 


THOUGHT,  OR  OBSERVATION,  QUESTIONS. 

How  does  the  thigh  bone  differ  from  the  shoulder  blade  ? 

What  is  the  reason  the  ridge  will  not  be  prominent  on  a  baby's 
thigh  bone? 

How  do  the  ends  of  a  thigh  bone  differ? 

What  is  the  difference  between  the  inside  of  the  shaft  and  of  the 
head  of  long  bones? 

What  is  the  difference  in  result,  if  you  place  one  bone  in  acid 
and  the  other  in  the  fire? 

If  it  were  possible  to  stop  up  all  the  outside  holes  in  a  live  bone, 
what  would  happen? 

What  is  the  difference  between  the  joints  of  the  head  and  those 
of  the  fingers? 


BONES.  35 

Name  all  the  places  where  ball  and  socket  joints  are  found. 
Which  part  of  the  body  is  best  protected  by  bone? 
Name  three  differences  between  a  rib  and  an  arm  bone. 
Why  can  ribs  be  pressed  out  of  position? 
Is  your  nose  all  cartilage  ? 

How  is  the  peg  of  the  second  vertebra  held  in  the  hollow  of  the 
first  vertebra  ? 

Name  four  differences  between  thigh  bone  and  lumbar  vertebra. 
Draw  a  thigh  bone,  a  vertebra,  a  hip  joint,  a  knee  joint,  a  scapula. 
What  is  the  difference  between  a  spine  and  a  vertebra  ? 


36  PHYSIOLOGY. 

CHAPTER  3. 

MUSCLES. 

Muscle,  or  flesh,  is  most  easily  seen  as  the  soft  tissue 
that  covers  bones.  It  is  in  rounded  masses  that  give 
shape  and  beauty  to  all  parts  of  the  body.  The  thick 
parts  at  the  base  of  the  thumb,  on  the  forearm  just  below 
the  elbow,  the  bunch  on  the  top  of  the  shoulder,  the 
masses  at  the  hip  and  the  calf  of  the  leg,  all  show  prom- 
inent surface  muscles  that  are  just  under  the  skin. 

Contractility. — Place  your  left  hand  on  the  front  of 
your  right  arm,  a  little  above  the  elbow,  and  bring  your 
right  hand  toward  your  shoulder.  Notice  how  hard  the 
muscle  gets.  Doubling  the  fist  hardens  the  muscles  just 
below  the  elbow.  Muscles  are  soft  when  not  in  action,  and 
become  hard  when  they  move.  They  also  thicken  and 
shorten.  This  is  the  peculiar  and  chief  characteristic  of 
muscle,  that  it  can  contract  or  draw  itself  up.  When  it 
contracts,  it  pulls  flesh,  bone,  or  whatever  else  is  con- 
nected with  it  toward  itself.  Move  the  fingers  of  your 
hand  backward  and  forward,  and  watch  your  wrist. 
Then  press  the  back  of  your  hand,  then  the  upper  part 
of  the  forearm.  Every  motion  of  the  fingers  is  con- 
trolled by  the  muscle  of  the  arm,  and  the  tendons  at  the 
wrists  and  back  of  the  hands  show  the  connection. 

Voluntary  and  Involuntary  Muscles.  —  Your 
fingers  open  and  shut;  your  hand  is  put  forth  and  drawn 
back;  you  walk  and  talk  when  you  will,  but  muscle  is 
the  mover.  The  heart  is  a  muscle.  Put  your  hand  on 
your  left  side,  and  feel  it  beat.  Your  will,  or  thought, 
has  no  control  over  its  beating.  Neither  does  any  one 
think  how  food  is  going  down  to  his  stomach  when  eat- 
ing, yet  it  is  pushed  along  by  muscular  action;  nor 


MUSCLES. 


37 


does  he  think  how  he  must  grow,  but  growth  is  largely 
dependent  upon  the  action  of  the  muscles.  Evidently, 
therefore,  while  some  muscles  are  controlled  by  the  will, 
others  are  not.  Those  of  the  first  class,  as  the  muscles 
of  the  face,  head,  outside  of  the  trunk,  and  the  extrem- 
ities, are  called  voluntary. 

The  muscles  of  the  internal  organs  are  not  controlled 
by  the  will.  The  heart  beats,  the  breath  comes  and  goes, 
the  blood  moves,  without  our  thinking.  All  these  acts 
are  performed  by  muscles  called  involuntary. 


FIG.  19.  Muscle  Fibres.— I.  Voluntary:  1.  Twisted  Fibre  of  Striped 
(Striated)  Muscle;  2.  Fibrils. 

II.  Involuntary:  3.  Unstriped  ( Unstriated)  Muscle;  4.  Single  Cells: 
5.  Nucleus  of  Cell. 

Structure. — Both  classes  of  muscles  are  made  of 
thread-like  fibres.  These  are  plainly  seen  in  lean  meat, 
and  give  it  its  stringy  appearance.  The  microscope 
shows  that  not  all  fibres  are  alike.  In  voluntary  muscles 
the  fibres  are  bundles  of  fine,  long  threads,  placed  side 


38 


PHYSIOLOGY. 


FIG.  20  (Copied). 


MUSCLES. 


39 


FIG  21  (Copied). 


40 


PHYSIOLOGY. 


by  side,  called  fibrils  ( Fig.  19,1.).  Each  fibril  is  made  of 
tiny  cells,  placed  end  to  end,  and  the  tops  of  the  cells 
form  fine  lines,  running  across  the  muscles  like  delicate 
stripes;  this  is  called  striped  muscle. 

MUSCLES. 

f  24.  Occipito  frontalis,  moves  the  scalp. 

23.  Orbicularis  palpebrarum,  puckers  up  eyelids. 
ad-  •  j  21.  Masseter,  lifts  under  jaw. 

20.  Digastric,  pulls  down  lower  jaw. 
1,22.  Orbicularis  oris,  puckers  up  the  lips. 

f25.  Sterno-cleido-mastoid,  bends  head  forward. 
19.  Trapezius,  pulls  head  backward. 
Trunk.   <j    2*  Pectoralis  major,  pulls  arm  forward. 
j    3.  Latissimus  dorsi,  pulls  arm  backward. 
|     5.  Serratus  magnus,  aids  in  respiration. 
(.    6.  Obliquus  externus,  aids  in  respiration. 

Jl.  Deltoid,  lifts  arm  up. 
3.  Biceps,  lifts  forearm  up. 
4.  Triceps,  pulls  forearm  down. 
(16.  Extensors,  extend  the  hand. 
17.  Flexors,  shut  the  hand. 
I  18.  Annular  ligament,  holds  tendons  in  place. 

8.  Rectus  femoralis,  pulls  leg  forward. 

15.  Biceps  femoralis,  pulls  leg  backward. 

9.  Sartorius,  crosses  the  legs. 

11.  Vastus  externus  and  internus,  extend  the  leg. 
Leg         j  ^'  Adductor,  raises  the  thigh. 

1     7.  Glutei,  lower  the  thigh. 

12.  Gastrocnemius,  extends  the  foot. 
14.  Tibialis  anticus,  flexes  the  foot. 

13.,,Tendo  Achilles,  connects  gastrocnemius  to  heel  bone. 

16.  Annular  ligament,  binds  down  tendon. 

Involuntary  muscle  cells  are  spindle-shaped  and  they 
overlap  at  the  ends  so  that  there  are  no  cross  lines,  and 
such  muscle  is  called  plain,  or  unstriped  (Fig.  19,  II.). 

The  cells  in  both  cases  are  composed  of  a  peculiar  jelly- 
like  substance  called  protoplasm,  which  is  found  in  all 
parts  of  the  body  where  there  is  growing  or  living 
tissue. 


MUSCLES.  41 

Each  fibre  has  around  it  a  coat  of  thin  tissue  called 
flesh  sheath,  which  binds  the  fibrils  together  (Fig.  22, 

11.  1).   Then  each  bundle  of  fibres  which  forms  a  sep- 
arate muscle  is  wrapped  in  a  fine,  white,  silky  membrane 
named  connective  tissue.     This  keeps  the  muscles  apart. 
This  tissue  can  be  seen  on  beef  or  mutton   "suet,    and 
may  be  torn  off  in  large,  papery  pieces. 

Shape  and  Arrangement. — Muscles  are  of  different 
shapes.  Sometimes  they  are  long,  roundish  masses  (1,7, 

12,  Figs.  20,  21);  sometimes  in  flat  bands   (11,  Fig.  20); 
or  ribbon-like  pieces  (9,  Fig.  20).     Those  that  work  the 
bones  are  often  arranged  one  over  the  other  in  irregular 
layers,  and  the  outside  ones  are  called  superficial  (2,  Fig. 
20),  and  the  under  ones,  deep-seated  (5,  Fig.  20). 

Action  of  Muscles. — The  striped  muscles  are  gen- 
erally in  pairs,  opposed  to  each  other,  so  that  they  coun- 
teract each  other's  motion.  One  pulls  a  part  of  the  body 
out  of  place,  and  the  other  brings  it  back  to  position. 
One  set  shuts  the  fingers  (17,  Fig.  20),  the  opposite  set 
pulls  them  open  (16,  Fig.  20);  one  lifts  the  arm^(l,  Fig. 
20),  the  other  pulls  it  down  (2,  Fig.  20);  one  moves  the 
head,  or  the  leg,  forward,  another  brings  it  backward. 

Flexors. — Double  up  your  fist.  You  have  willed  that 
the  muscles  on  the  front  of  your  forearm  shall  contract. 
They  bunch  up  and  pull  on  the  tendons  that  pass  along 
the  front  of  the  wrist  (17,  Fig.  20)  to  the  many  finger 
bones.  Then  the  fingers  double  up.  A  muscle  that  does 
such  work  is  called  a  flexor.  Flexors  are  found  in  the 
extremities. 

Extensors. — When  you  will  to  open  your  hand  a  set 
of  muscles  on  the  back  of  the  forearm  contracts,  the  flex- 
ors relax,  and  the  tendons  on  the  back  of  the  hand  (16, 
Fig.  20)  pull  on  the  bones  and  straighten  the  fingers. 


42  PHYSIOLOGY. 

These  muscles,  which  extend  the  fingers  and  hand,  are 
called  extensors. 

Although  the  terms  extensor  and  flexor  apply  only  to 
muscles  of  the  arms  and  legs,  there  are  many  pairs  of- 
muscles  in  the  body  acting  in  much  the  same  way. 
Sometimes  they  act  together,  to  keep  the  head  or  body 
erect. 

Lift  your  arm  over  your  head.  The  large  muscle  on 
the  top  of  the  shoulder  does  it  (1,  Fig.  20).  Muscles  on 
each  side  of  the  armpit,  acting  together,  bring  it  down. 
Work  your  arm  slowly,  as  though  hammering,  and  feel 
the  muscles  on  the  back  and  front  of  the  arm  contract 
and  relax  in  turn.  The  muscle  on  the  front  is  called 
biceps  (3,  Fig.  20),  and  is  the  one  that  active  and  ath- 
letic boys  are  very  proud  of  showing  when  they  say,  "  feel 
my  muscle."  Its  counteractor  is  triceps  (4,  Fig.  20). 

Muscular  Training. — Playing  ball,  rowing,  and  dif- 
ferent gymnastic  exercises,  develop  arm  muscles,  and 
walking  and  jumping  are  good  for  developing  leg  muscles. 

Muscles  are  the  movers  of  the  body.  The  voluntary 
class  has  to  be  taught  to  work.  Grown  people,  who  walk 
and  talk  and  move  about  freely,  quickly,  and  fearlessly, 
forget  that  they  have  to  use  their  wills  in  order  to  move; 
but  if  we  watch  a  baby  trying  to  walk,  talk,  or  hold  a 
toy,  or  aimlessly  seeking  to  reach  for  something  bright, 
in  other  words  trying  to  teach  his  muscles  to  work,  we 
are  able  to  appreciate  the  amount  of  skill  our  own  mus- 
cles have  acquired. 

Color. — Muscles  are  generally  pinkish  in  color,  and 
dark  or  light  according  to  the  amount  of  exercise  given 
them.  This  can  be  seen  by  comparing  the  breast  mus- 
cles of  game  birds,  like  quail  and  wild  duck,  which  use 
their  wings  a  great  deal,  with  the  same  muscles  of  chick- 
ens, which  rarely  fly.  Exercise  makes  muscles  dark, 


MUSCLES.  43 

full,  and  hard,  but  laziness  causes  them  to  be  pale  and 
flabby. 

Tendons. — Muscles  rarely  unite  directly  with  bone, 
but  taper  oft'  and  are  connected  with  it  by  means  of 
tough,  white  connective  tissue,  called  tendons.  They  are 
also  called  leaders,  thews,  cords,  or  sinews.  There  are 
two  advantages  in  having  muscle  end  in  tendon:  First, 
by  the  tapering  of  a  bulky  muscle,  less  room  is  occupied, 
and  the  body  is  more  symmetrical  and  shapely;  and, 
second,  there  is  a  concentration  of  force  at  one  point. 

Tendons  are  inelastic.  They  are  sometimes  cord-like 
and  sometimes  in  flat  bands.  They  can  be  seen  in  Figs. 
20,  21,  at  the  end  of  the  muscles.  They  are  prominent 
and  near  enough  the  surface  to  be  seen  and  felt  at  the 
wrist,  back  of  the  hand,  back  of  the  knee,  and  heel  and 
ankle. 

They  are  bound  down  at  the  wrist  and  ankle  and  kept 
from  springing  outward,  when  the  fingers  or  toes  are 
worked,  by  a  kind  of  living  bracelet  called  annular  liga- 
ment (18,  Fig.  20). 

They  are  large  where  much  strength  is  required.  The 
leg  muscles  support  the  weight  of  the  body,  and  their 
tendons  are  larger  than  those  of  the  arms.  Notice  how 
strong  the  one  is  that  connects  the  heel  bone  with  the 
muscle  that  forms  the  calf  of  the  leg  (13,  Fig.  21).  It 
is  the  largest  in  the  body. 

Cutting  of  Tendons. — Tendons  are  also  large  on 
each  side  of  the  back  of  the  knee.  Here  they  are  some- 
times called  "ham  strings."  Formerly,  in  more  barbar- 
ous times,  cruel  people  tortured  their  enemies  or  innocent 
people  whom  they  hated,  by  cutting  these  strong  cords. 
This  destroyed  the  balance,  and  the  tendon  connected 
with  the  muscle  on  the  front  part  of  the  leg  pulled  the 
leg  forward  and  the  injured  person  was  never  able  to 
walk  or  stand  again. 


44  PHYSIOLOGY. 

Band  Tendons. — The  tendon  of  the  muscle  that 
moves  the  scalp  is  an  example  of  the  flat  band.  Its 
arrangement  is  unusual.  It  is  between  the  two  parts  of 
muscle  seen  in  24,  Fig.  20.  The  muscle  fibres  begin  and 
are  attached  to  the  bone  at  the  eyebrows  and  continue 
over  the  forehead;  then  the  broad  band  over  the  top  of 
the  skull  is  tendon,  which  ends  in  muscle  that  is  fastened 
to  the  bone  at  the  back  of  the  head. 

Involuntary  Muscles. — Involuntary  muscles  are 
generally  inside  the  trunk,  and  are  connected  with  bones, 
other  muscles,  or  other  organs.  They  are  often  in  fibrous 
rings  or  bands,  in  the  walls  of  organs  that  contract  and 
enlarge,  as  in  the  walls  of  blood  vessels,  and  of  the  stom- 
ach and  the  intestines.  They  are  an  important  part  of 
the  vital  organs  that  control  the  food  and  the  nourish- 
ment of  the  whole  system,  and  of  the  breathing  organs, 
and  of  those  that  make  the  blood  circulate.  It  is  exceed- 
ingly fortunate  that  the  muscles  which  direct  the  circula- 
tion of  the  blood,  respiration,  and  the  distribution  of  food 
act  without  our  thinking  to  tell  them,  for  were  it  other- 
wise we  could  get  no  time  to  think  of  anything  else.  Day 
and  night,  whether  we  sleep  or  wake,  play  or  rest,  these 
involuntary  muscles  must  keep  moving  to  build  up  or 
renew  the  tissues.  So  long  as  we  use  judgment  in  taking 
proper  food,  drink,  rest,  and  exercise,  and  in  keeping  clean 
bodies  and  pure  minds,  these  patient  workers  work  on, 
and  work  well,  and  keep  us  healthy  and  happy.  The 
largest  and  most  remarkable  of  this  class  are  the  heart 
and  the  diaphragm. 

The  Heart. — The  heart  is  a  single  muscle,  and  its 
fibres  have  characteristics  that  place  them  between  the 
voluntary  and  involuntary  classes.  They  have  no  flesh 
sheath,  are  branched,  the  fibrils  are  finer,  and  the  stripes 
more  delicate  than  in  striped  muscle  (Fig.  22).  They 


MUSCLES. 


45 


look  more  like  striped  than  unstriped,  but  they  are  not 
under  the  control  of  the  will. 

The  Diaphragm. — In  5,  Fig.  ^&,  a  portion  of  the 
diaphragm  is  shown,  dividing  the  upper  part  of  the  trunk, 
or  chest,  from  the  lower  part,  or  abdomen.  It  is  a  thin, 
muscular  partition,  joined  to  the  ribs  and  back  bone  and 
muscular  walls  of  the  front  of  the  trunk.  It  is  made  of 


I.  II. 

FIG.  22.— I.  Muscle  Fibres  from  Tongue :  1.  Muscle  Sheath  (Sarco- 
lemma) ;  2.  Stripes  (Strix) ;  3.  Fibril. 

II.  Muscle  from  Heart  (showing  cross  divisions  and  branching 
arrangement):  2.  Striae;  4.  Nucleus. 

coarse,  involuntary  muscular  fibres.  It  is  an  important 
agent  in  breathing,  and  it  readily  changes  shape.  When 
air  is  expired  and  the  chest  is  contracted,  the  diaphragm 
is  dome-shaped;  when  the  chest  is  full  of  air,  the  dia- 
phragm is  flattened.  Above  it  are  the  lungs  and  heart, 
and  below  are  the  stomach,  liver,  and  intestines.  All 
the  long  tubular  organs,  such  as  the  food  canal  and  the 
blood  vessels,  which  extend  the  length  of  the  trunk,  pass 
through  the  diaphragm  as  large  tubes. 

Connective   Tissue. — The    membrane    that    wraps 


46  PHYSIOLOGY. 

around  muscle  is  called  connective  tissue.  It  is  one  of 
the  most  widely  distributed  materials  of  the  body  and 
varies  in  use  and  appearance.  It  forms  a  cover  and  a 
lining  for  all  organs,  and  is  the  framework  upon  which 
all  soft  parts  are  formed,  and  in  which  the  character- 
istic cells  of  other  tissues  (Fig.  3)  are  placed,  and  through 
which  the  network  of  nerves  and  blood  vessels  is  inter- 
woven. 

It  seems  to  be  the  basis  of  everything.  It  has  been 
said  that  if  it  were  possible  to  take  away  all  other 
tissues,  the  connective  would  retain  the  shape  of  the 
whole  body  and  be  a  perfect  mold  of  all  the  organs.  It 
wraps  around  the  bones,  nerves,  fat,  and  muscles.  It 
forms  part  of  the  walls  of  blood  vessels,  and  the  frame- 
work of  skin,  tendon,  and  ligament;  under  the  name  of 
serous  membrane  it  lines  the  trunk  and  brain  box,  and 
shuts,  in  a  separate,  closed  sac,  each  vital  organ,  as  the 
lungs,  heart,  stomach,  and  intestines. 


FIG.  23.  Fat  (Adipose)  Tissue  (cells  crowded).— Thin  connective  tis- 
sue full  of  fat  with  oval  masses  of  crystals. 

It  is  sometimes  tough  and  compact  and  fibrous,  as  liga- 
ment and  tendon,  but  generally  it  is  fine  and  thin  and  full 
of  many  roundish  openings  (Fig.  23).  These  openings 
are  not  holes,  but  large,  elastic  spaces,  connected  together. 


MUSCLES.  47 

In  some  diseases,  as  in  dropsy,  an  excess  of  watery 
fluid  gets  into  this  tissue  and  gives  the  person  a  swelled 
and  puffy  appearance.  Butchers  sometimes  insert  tubes 
between  muscles  of  veal  and  blow  the  cellular  connective 
tissue  full  of  air  to  make  the  meat  look  plump.  It  is 
then  called  "  blown  veal." 

Fat.— Fat  is  a  substance  stored  up  in  the  connective 
tissue  of  many  parts  of  the  body.  It  is  inert  and  seems 
to  be  merely  a  kind  of  food  packed  away  for  a  time  of 
need.  It  is  found  as  yellowish  masses  around  organs,  or 
in  liquid  globules  stored  among  the  tissues  of  all  parts 
of  the  body. 

Under  the  microscope  it  shows  as  roundish  cells. 
Sometimes,  on  cooling,  it  forms  bunches  of  crystals  that 
cluster  together  in  oval  masses  (Fig.  23).  Its  accumula- 
tion about  the  vital  organs  often  interferes  with  their 
function. 

THOUGHT,  OR  OBSERVATION,  QUESTIONS. 

Name  three  characteristics  common  to  both  kinds  of  muscles. 
Draw  both  kinds. 

Why  is  a  chicken's  breast-meat  lighter  colored  than  its  legs? 

In  how  many  ways  does  tendon  differ  from  bone?  Can  tendon 
stretch? 

If  the  tendon  above  the  kneepan  were  cut,  what  two  things  would 
happen,  and  why? 

What  parts  of  muscle  are  microscopic? 

What  muscles  are  used  when  a  beggar  puts  out  his  hand  for 
money? 

What  happens  when  he  gets  it? 

What  is  the  difference  between  the  muscles  that  cause  food  to  be 
chewed  and  those  that  move  it  around  in  the  stomach? 

Name  four  differences  between  breast  and  tongue  muscle. 


48 


PHYSIOLOGY. 


CHAPTER  4. 

THE    SKIN   AND   ITS   APPENDAGES. 

The  Skin. — Fig.  24  shows  how  the  human  skin  looks 
when  it  is  magnified  many  times.  It  is  an  elastic 

tissue   which  loosely   covers   the      ft}/    outside  of  the 


FIG.  24.  Section  of  Skin.— 1.  Shaft  of  Hair;  2.  Medullary  Substance; 


13.  Muscle;  14.  Nerve. 

body  and  is  fastened  to  the  muscles  by  connective  tissue. 
The  lower  layer  is  full  of  nerves  and  blood  vessels.  You 
will  find  that  it  is  loose  and  elastic  by  pinching  it  up  on 


THE  SKIN  AND  ITS  APPENDAGES.  49 

the  face  or  hands.  Blood  vessels  can  be  seen  as  bluish 
cords  standing  up  in  many  places,  and  5,  Fig.  21,  shows 
how  they  branch.  If  cut  they  bleed.  A  cut  or  scratch 
causes  pain,  and  that  shows  that  there  are  nerves. 

Mucous  Membrane. — Membrane,  like  the  skin,  but 
somewhat  modified,  lines  the  inside  of  the  body,  so  that 
the  outside  coat  and  the  inside  lining  are  continuous. 
The  lips  show  how  the  two  membranes  meet.  The  out- 
side one  covering  the  muscles  is  called  skin,  but  when  it 
lines  the  air  passages  of  nose,  throat,  and  lungs,  and  the 
food  passages  of  the  mouth  and  digestive  canal,  it  is  called 
mucous  membrane. 

The  difference  between  skin  and  mucous  membrane  is 
well  shown  at  the  lips  and  on  the  inside  and  outside  sur- 
face of  the  eyelids.  Mucous  membrane  is  thinner,  more 
moist,  and  fuller  of  blood  vessels  than  skin.  It  looks  red, 
because  the  many  blood  vessels  show  through. 

Mucous  membrane  lines  passages  into  which  air  can 
get.  It  is  very  different  in  different  places,  but  no  matter 
what  its  form  is,  it  is  nothing  but  skin  changed  so  that 
it  can  do  many  kinds  of  work.  Its  modifications  can  be 
best  studied  with  the  subjects  of  digestion  and  respira- 
tion. 

Cuticle. — The  skin  is  made  of  two  parts.  The  outer 
part  is  called  the  external,  or  scarf,  skin,  epidermis,  and 
cuticle.  Little  pieces  can  be  cut  off  the  skin  of  the  fingers 
without  drawing  blood  or  causing  pain,  because  it  has 
neither  nerves  nor  blood  vessels.  It  is  often  loosened 
from  the  lower  skin  by  a  burn  or  a  blow,  and  this  causes 
what  is  called  a  blister.  The  bruise,  or  burn,  shows  the 
thin  cuticle  freed  from  the  inner  skin,  with,  at  first,  a 
liquid  between  them.  If  the  blister  is  cut  it  causes  pain, 
for  then  the  tender  under  skin  is  exposed  to  the  air. 

A  blood  blister  is  different  from  an  ordinary  blister. 

4— P 


50  PHYSIOLOGY. 

It  is  caused  by  a  blow,  which  bruises  the  under  skin  and 
breaks  some  of  the  tiny  blood  vessels.  They  bleed,  the 
blood  collects  between  the  two  layers  of  skin,  and  the 
blister  looks  red  at  first,  then  turns  dark  as  it  gets  old. 

Cells  of  Cuticle.— The  cuticle,  or  little  skin,  like  all 
other  tissues,  is  made  of  cells.  These  are  flatter  and  drier 
than  the  cells  of  the  under  layer.  The  difference  between 
the  very  flat,  horny,  worn-out  cells  of  the  upper  part  of  the 
cuticle  and  the  more  rounded  ones  near  the  true  skin  is 
shown  in  Figs.  24,  27. 

You  can  remove  and  see  the  small  scales  of  cuticle 
by  rubbing  a  black  cloth  on  the  face.  They  are  being 
rubbed  off  all  the  time.  As  they  dry  and  wear  away, 
new  ones  grow  constantly  from  below.  On  the  head  the 
loose  scales  are  called  dandruff. 

Generally  the  scarf  skin  is  removed  insensibly  in 
small  particles,  by  bathing  and  by  the  friction  of  clothing; 
but  sometimes,  as  after  fevers,  it  peels  off  in  large  patches 
or  tatters.  Children,  who  have  had  scarlet  fever,  often 
speak  of  it  as  "  skinning." 

Thickened  Cuticle. — The  cuticle  is  thin  over  most 
parts  of  the  body,  but  in  places  which  are  much  rubbed 
or  pressed,  as  at  the  soles  of  the  feet,  it  is  thickened* 
People  who  are  not  used  to  hard  work  get  the  palms  of  the 
hands  hardened  in  patches,  or  even  blistered,  by  sweeping 
or  rowing.  In  case  of  blistering,  the  friction  rubs  the 
upper  skin  loose.  If  such  hard  work  is  done  constantly, 
the  skin  of  the  hands  becomes  thick,  horny,  and  callous. 
Notice  where  the  cuticle  is  thickest  in  your  hand. 

The  pressure  of  badly-fitting  boots  acts  much  the  same 
as  hard  work  does  on  hands,  and  rubs  painful,  hard  places, 
called  corns,  on  the  toes.  This  happens  when  boots  are 
too  tight,  or  too  loose,  and  is  caused  by  the  effort  of  the 
cuticle  to  place  something  between  the  tender  under  skin 


THE  SKIN  AND  ITS  APPENDAGES.  51 

and  the  irritating  leather.     Thickened  cuticle  generally 
acts  as  a  protector. 

Pigment. — The  lower  layer  of  cells  of  scarf  skin  fol- 
lows closely  the  outline  of  the  under  skin,  and  it  is 
generally  well  supplied  with  little  dark  colored  grains. 
It  is  called  the  pigment,  or  paint  layer  (9,  Fig.  24). 
Pigment  grains,  like  thickened  cuticle,  are  for  protecting 
the  inner  skin.  They  guard  it  from  the  injurious  effect  of 
too  much  sunlight. 

Complexion. — Fair  people  have  little  pigment,  and 
dark  ones  have  much.  In  the  Indian,  negro,  and  other 
dark  races,  the  pigment  layer  is  thicker,  and  there  are 
more  grains  of  coloring  material  than  in  light  colored 
people.  Albinos  have  no  pigment.  They  are  persons,  or 
lower  animals,  having  white  hair,  pink  eyes,  and  pinkish 
or  chalky  white  skins  or  fur.  White  rats  and  rabbits  are 
good  examples.  Because  pigment  is  wanting,  the  color 
of  the  blood  is  seen  in  the  eyes,  making  the  eyes  look 
pink.  When  the  cuticle  is  thin,  the  skin  looks  pinkish 
for  the  same  reason. 

Tan  and  Burn. — Sunlight  either  produces  some 
change  in  the  pigment,  or  increases  its  amount,  so  that 
persons  who  live  much  out  of  doors  get  their  complexions 
darkened.  Those  who  stay  indoors  too  much  become 
bleached.  Sunburn  is  caused  by  the  heat  of  the  sun 
bringing  a  quantity  of  blood  to  the  surface.  If  people 
who  have  thin  skins,  or  very  little  pigment,  are  exposed 
very  long  to  sunlight,  the  burn  becomes  painful,  and 
blisters  like  any  other  burn.  Most  people  with  dark 
complexions,  being  better  protected  by  pigment,  merely 
tan,  or  darken.  Sometimes  sunlight,  or  wind,  causes 
the  pigment  to  form  in  small  specks,  called  freckles. 
Freckles  come  and  go  according  to  the  amount  of  expos- 
ure. Generally  as  people  grow  older  less  pigment  is 


52  PHYSIOLOGY. 

formed,  the  face  becomes  paler,  and  sunshine  does  not 
cause  freckles. 

Scars. — When  the  pigment  layer  is  destroyed  in  any 
place, it  will  not  form  again;  so  when  a  cut  is  deep  enough 
to  injure  it,  the  scar  that  forms  always  stays  white.  This 
is  true  of  light  or  dark  skins,  and  a  very  deep  cut  on  a 
negro  heals  whitish. 

Outis. — The  under  skin  is  called  cutis,  dermis,  or  true 
sHn.  It  begins  just  below  the  pigment  layer.  It  is  a 
loose  network  of  fibres  and  cells  full  of  branching  nerves 
and  blood  vessels.  These  vessels  are  so  crowded  together 
that  it  is  impossible  to  cut  the  dermis  without  drawing 
blood  and  causing  pain. 

Papillae. — The  upper  surface  of  the  dermis  is  not  level 
like  that  of  the  cuticle,  but  is  made  of  a  multitude  of  lit- 
tle projections  called  papillse  (singular,  papilla}.  (8, 
Fig.  24.)  Of  course,  they  are  microscopic.  Although 
they  are  so  small  that  you  cannot  see  them  with  the 
unaided  eye,  they  are  filled  with  tiny  blood  vessels,  which 
make  this  part  redder  than  any  other  portion  of  the 
skin.  They  also  contain  the  tips  of  the  nerves  of  touch. 

In  very  sensitive  places  the  papillae  are  crowded 
together,  but  in  places  where  there  is  not  much  feeling 
they  are  far  apart.  Notice  the  ends  of  your  fingers. 
The  ridges  are  rows  of  papillae.  The  rows  are  curved 
around  in  a  queer  way.  There  are  so  many  termina- 
tions of  nerves  in  these  rows  that  you  can  feel  better  with 
the  ends  of  the  fingers  than  with  any  other  part  of  the 
hand. 

Appendages. — There  are  certain  organs  called  ap- 
pendages of  the  skin.  They  are  hair,  nails,  teeth,  the  oil 
and  the  sweat  glands.  They  are  modifications  of  skin. 
Teeth,  like  hair,  are  modified  skin.  They  grow  from 


THE  SKIN  AND  ITS  APPENDAGES. 


53 


UU—i  papilla?  in  folds 

of  the  skin,  and 
therefore  belong 
to  this  system; 
but      as     their 
function  is  to  pre- 
pare food,  they  are 
best   studied  with 
the  digestive  system. 

Hair. — Hair  is  mod- 
ified cuticle.  Each  hair 
grows  in  a  long  tube  that 
is  a  depression  of  the 
cuticle  which  extends  from 
the  surface  down  deep  into 
the  cutis  (Fig.  25).  This 
tube  is  called  a  hair  sac.  The 
lower  end  of  each  hair  fits  like 
a  cap  over  one  of  the  papillae 
of  the  cutis,  and  grows  from 
it.  If  a  papilla  is  destroyed 
no  new  hair  will  ever  grow  in 
that  place.  Each  hair  is  made 
of  three  parts:  the  shaft,  above 
the  surface;  root,  below  the 
surface;  and  bulb,  at  end  of 
root.  Pull  out  a  hair  from 
your  head  and  tell  how  the  end  of  the  root  differs  from 
the  shaft. 

The  hair  is  destitute  of  nerves  and  blood  vessels.  It 
hurts  sometimes  to  pull  it  out,  because  there  are  nerves 
in  the  papillae,  which  are  injured  when  the  hair  bulb  is 
torn  loose.  Nearly  all  the  body  is  clothed  with  fine  hair 
or  down.  None  is  found  on  the  palms  of  the  hands,  or 


FIG.  25.— 1.  Shaft  of  Hair;  2. 
Dry  Cells  of  Epidermis;  3.  Pig- 
ment Layer;  4.  Papilla;  5. 
True  Skin  (Dennis};  6.  Root  of 
Hair;  7.  Bulb  of  Hair;  8.  Fat 
Cells;  9.  Muscle;  10.  Blood 
Vessels;  11.  Depression  of  the 
Cuticle,  Hair  Sac,  or  Follicle. 


54 


PHYSIOLOGY. 


soles  of  the  feet,  or  the  first  joints  of  fingers  and  toes. 

The  eyelashes  are  short,  stiff 
hairs. 


I. 


II. 


III. 


FIG.  26.— I.  Outside  of  Brown  Hair. 


II.  Outside  of  Gray  Hair  (Medullary  center  (3)  shows  through). 

III.  Cross  Sections  of  Hair:  1.  Scaly  outside  (Cortex};    2.  Cellular 
part  (Fibrous,  or  of  long  cells);  3.  Medullary  part  (Roundish  cells). 

Do  these  hairs  stand  with  the  top  up,  or  the  root? 

Structure. — A  hair  is  not  perfectly  round  (Fig.  26). 
It  is  cellular  and  fibrous  inside,  but  not  hollow.  The 
cells  contain  air,  water,  oil,  and  pigment  grains.  The 
outside  part  has  irregular  scales,  and  the  free  ends  of 
these  are  turned  toward  the  tip  of  the  hair.  When  a 
hair  is  held  by  the  tip  it  can  be  cut  with  a  sharp  knife, 
but  the  knife  slips  off  the  scales  if  it  is  held  by  the  root. 
The  roughness  can  be  felt  by  pulling  a  hair  through  the 
fingers  from  tip  to  root. 

Changes  in  Hair. — The  sun  bleaches  hair,  or  makes 
it  rusty,  and  damp  weather  causes  curly  hair  to  curl 
tighter.  Like  epidermis,  it  is  renewed  by  degrees,  except 
in  sickness  and  old  age,  when  it  often  all  comes  out.  It 
shows  ver^  few  signs  of  life,  but  cannot  be  considered 
entirely  dead  material,  because  its  condition  changes  with 
the  change  from  health  to  illness  of  a  person.  When  it  is 
dry.  harsh,  and  brittle,  there  is  some  trouble  with  the  gen- 


THE  SKIN  AND  ITS  APPENDAGES.  55 

eral  skin  system,  while  soft  and  glossy  hair  indicates  that 
this  system  is  in  good  working  order. 

There  is  no  doubt  that  some  material  works  its  way 
from  the  papillae  through  the  cells  of  hairs  even  after 
they  are  full  grown,  under  the  influence  of  the  nerves. 
This  is  shown  by  the  fact  that  hair  changes  from  dark 
to  white  before  old  age,  under  the  influence  of  some 
severe  emotion,  as  fear,  or  fright,  or  as  the  result  of  ex- 
tremely exhaustive  labor  or  dissipation. 

These  things  greatly  affect  the  nervous  system,  and  the 
nerves  control  the  circulation  of  blood.  Now,  if  there 
is  too  great  a  demand  for  blood  in  any  place,  other  parts 
suffer  want.  So,  if  overwork  or  fright  calls  the  blood 
away  from  the  papillae,  ordinary  conditions  are  interfered 
with,  some  mischief  begins,  and  the  hair  cells  are  filled 
with  air,  or  some  change  not  well  understood  is  made  in 
the  pigment,  and  the  color  is  lost.  The  change  of  color 
is  generally  slow.  Fig.  26  shows  how  brown  and  white 
hair  differ  under  the  microscope.  The  cells  full  of  air  in 
the  center  of  the  white  hair  look  black  when  seen  through 
a^  microscope. 

Why  Hair  "Stands  on  End."— There  are  small 
muscles  connecting  the  upper  part  of  the  skin  with  the 
lower  portion  of  each  hair  sac  (9,  Fig.  25).  When  these 
contract  they  pull  up  the  sac,  and  the  hair  is  said  "to 
stand  on  end."  Cold,  fright,  or  electricity,  cause  them 
to  contract.  On  cold  days,  if  the  arms  are  exposed  to 
the  air,  they  get  pimply  from  this  cause,  and  are  said  to 
be  all  "goose  flesh."  Probably  the  same  muscles  act  and 
cause  the  hair  along  the  back  of  a  dog's  neck  to  stand  up 
when  he  is  attacked  by  another  dog. 

Nails. — Nails  are  another  modification  of  cuticle. 
They  are  of  the  same  flexible,  horny  material  as  the 
hoofs  and  horns  of  some  lower  animals.  They  are  curved 


56  PHYSIOLOGY. 

from  side  to  side,  and  extend  over  the  ends  of  the  fingers 
and  the  toes.  They  grow  from  a  fold  of  skin  which  fits 
closely  along  each  side  and  the  base.  They  are  flat  and 
wide  and  thin,  thus  differing  from  hair  in  shape,  but  they 
grow  from  papillae  in  the  same  way,  and  have  about  the 
same  composition  as  hair.  They  are  transparent,  and  the 


FIG.  27.  Cross  section  of  part  of  Nail  and  Finger,  showing  that  Nail 
is  modified  Epidermis.— 1.  Papilla  under  skin ;  2.  Pigment ;  3.  Cuti- 
cle; 4.  Nail;  5.  Lower  layer  of  cuticle;  6.  Papillae. 

blood  shows  through  and  makes  them  look  pink.  At  the 
base  there  are  fewer  papillae,  and  that  leaves  a  little  half- 
moon  place  that  is  whitish.  Like  hair,  teeth,  and  cuti- 
cle, they  are  without  nerves  and  blood  vessels.  Nails  ate 
protectors  of  the  ends  of  fingers  and  toes,  and  they  also 
aid  in  picking  up  small  articles. 

Growth. — The  nails  grow  rapidly,  but  probably  the 
rate  of  growth  differs  in  different  seasons  and  conditions 
of  health,  and  with  different  persons.  It  is  easy  to  time 
the  growth  by  putting  an  indelible  ink  mark  on  the  nail 
just  above  the  skin  and  noting  how  long  it  will  take  the 
stain  to  grow  to  the  end  of  the  finger.  If  pulled  out 
they  will  grow  again,  the  same  as  hair,  if  the  papillae  are 
not  injured. 

Sometimes  from  pressure  of  boots,  or  from  a  blow,  toe 
nails  are  injured,  and  they  remain  in  place  till  new  ones 
grow  under  them  and  loosen  them  off,  much  as  milk 


THE  SKIN  AND  ITS  APPENDAGES.  57 

teeth  are  pushed  out  by  permanent  ones.  It  takes  some- 
times as  much  as  four  or  five  months  for  new  ones  to 

grow.  The  growth,  as  well  as 
other  things,  shows  that  nails, 
hair,  and  teeth  are  modifications 
of  the  same  material.  Examine 
Figs.  24,  25,  27,  28,  for  papillae. 

Glands. — There  are  two  other 
very  important  parts  of  the 
skin:  the  oil  and  the  perspira- 
tion glands. 

A  gland  is  a  cellular  organ, 
which  has  the  power  of  taking 
materials  from  the  blood,  from 
which  it  makes  a  new  fluid. 

Secretion  and  Excretion. — 

Some  glands  take  waste  sub- 
stances, and  the  new  fluid  they 
make  must  leave  the  body,  or  it 
will  poison  it;  other  glands 
FIG.  28.  Development  of  make  materials  that  are  neces- 

P^Cavit^l^-RoT;  Milk    sary  to  the  growth  and  health  of 

Tooth);    3  Mucous    Mem-   the  body      Giands  are  said  to 

brane  of  Gum;    5.  Bone  of  J 

Jaw;   6.  Young  Tooth  (Per-   secrete,  or  hide,  their  fluids,  and 

from  this  some  of  the  fluids  are 

called  secretions.  Some  of  the  secretions  are  called  excre- 
tions, because  they  are  sent  out  of  the  system.  The  glands 
that  make  fluids  have  little  pipes  leading  from  them  for 
carrying  their  liquids  away.  These  are  called  ducts.  A 
duct  is  a  tube  or  canal.  Perspiration  is  an  excretion,  a 
waste  product;  and  oil  is  a  secretion,  a  fluid  needed  to 
keep  the  skin  pliable. 

Oil  Glands.— The  oil  glands  (Figs.  24,  29)  are  rather 


58  PHYSIOLOGY. 

short  and  thick,  and  have  a  branched,  sac-like  appear- 
ance. Sometimes  their  ducts  open  on  the  surface,  but 
oftenest  as  shown  in  Fig.  24.  They 
are  numerous  all  over  the  body, 
except  at  the  palms  of  the  hands 
and  the  soles  of  the  feet.  Their 
absence  allows  hands  that  are 
much  in  hot  water,  like  those  of  a 
washer-woman,  to  become  wrinkled 
and  shrunken  on  the  inside.  The 
oil  made  by  these  skin  glands  keeps 
the  skin  soft  and  pliant,  and  the 
hair  soft  and  glossy. 

Enough  is   secreted   and  poured 
FIG  29  Oil  Gland  —   over  ^e  hair  to  keep  it  soft  under 
(One   branch  cut   open    ordinary  circumstances,  so  that  the 
showing  cellular  lining.)  I 

habit  of  putting  oil  or  water  on  the 

hair  to  dress  it  is  useless  and  injurious.  Water  evap- 
orates soon,  and  leaves  the  hair  harsh  and  dry,  and,  if 
the  hair  is  very  thick,  it  gives  it  an  unpleasant  odor. 

Ear  wax  is  a  thick,  yellowish  oil,  that  is  secreted  by 
special  oil  glands  in  the  outer  part  of  the  ear.  It  is  bit- 
ter, and  for  this  reason  is  useful  in  keeping  insects  from 
crawling  into  the  opening  of  the  ear. 

Perspiratory  Glands. — The  other  set  of  skin  glands 
are  the  sweat,  or  perspiratory,  glands.  They  are  thin, 
long,  coiled  tubes.  They  open  obliquely  on  the  surface 
by  little  mouths.  These  openings,  with  those  of  the  oil 
glands,  are  called  pores  of  the  skin.  They  are  very  nu- 
merous. Sometimes  they  are  large  enough  to  be  seen,  as 
around  the  sides  of  the  nose,  where  they  become  filled 
with  dirt  and  appear  as  black  specks.  In  some  places, 
they  are  placed  in  regular,  curved  lines;  in  others,  they 
occur  irregularly,  as  in  Fig.  30.  Perspiration  regulates 


THE  SKIN  AND  ITS  APPENDAGES. 


59 


the  temperature  of  the  body,  and  removes  harmful  sub- 
stances. 

Sensible  Perspiration.— The  perspiration  which 
they  empty  on  the  surface  is  made  of  some  water,  some 

salty  material,  some  waste 
organic  matter,  and  some 
gas.     It   is   going  out 
of  the  pores  all  the 
time.     It  is  a  waste 
product.  •   When  it 

— -^rijs    ""T&m  me  ^    oozes   out    s°    fast 

0^6-Q  VDO  .^C^lf   that    it    cannot   be 

dried  away  by  the 
air,  and  collects  on 
the    hands,    upper 
FIG.  30.    Pores  of  Skin  (from  Arm).  ]ip?  anc[  forehead,  as 

drops  or  "  beads  of  sweat,"  it  is  called  sensible  perspira- 
tion, and  is  caused  by  over  excitement,  over  heating, 
or  over  exertion.  Also,  on  hot,  moist  days,  when  evap- 
oration goes  on  slowly,  it  becomes  visible.  All  these 
things  cause  the  blood  to  rush  to  the  surface,  and  the 
blood  vessels  being  full,  press  against  the  perspiratory 
glands,  and  make  them  send  out  a  larger  supply  than 
can  be  evaporated. 

Insensible  Perspiration. — When  perspiration  cannot 
be  seen  or  felt,  it  is  called  insensible.  Its  presence  can  be 
shown  by  placing  the  hand  on  a  cold  glass,  or  stone,  or 
polished  metal,  or  even  varnished  wood,  where,  if  the  day 
is  cool,  it  leaves  a  damp  outline. 

Evaporation. — If  you  put  a  drop  of  water  on  the  back 
of  your  hand  and  blow  on  it,  it  dries  away.  That  is 
evaporation.  If  perspiration  is  constantly  evaporating, 
it  is  one  means  of  keeping  cool.  You  can  prove  that  evap- 
oration cools  by  putting  water  on  one  hand  and  blowing 


60  PHYSIOLOGY. 

it,  and  then  blowing  on  the  other  hand  where  there  is 
no  water. 

Absorption. — The  pores  not  only  allow  oil  and  per- 
spiration to  reach  the  surface,  but  they  also  let  other  sub- 
stances enter  the  body  and  get  into  the  blood.  They 
absorb  anything  on  the  skin.  Sometimes  medicine  is 
given  in  this  way,  by  rubbing  it  on  the  surface.  The  pores 
let  it  in,  then  another  set  of  vessels  carries  it  to  the  blood 
tubes,  and  then  it  is  circulated  around  the  body  till  it 
reaches  the  part  that  needs  helping. 

Liquids  are  taken  up  freely.  Thirst  can  be  relieved  by 
wrapping  wet  cloths  around  the  body.  Shipwrecked  sail- 
ors who  could  not  drink  the  salt  water  around  them,  have 
been  greatly  refreshed  by  plunging  their  entire  bodies  in 
the  sea.  Sometimes  this  power  of  absorption  does  great 
harm.  Poisons  work  their  way  through  pores  as  easily  as 
do  substances  that  are  harmless.  This  is  especially  so  of 
the  pores  on  the  inside  of  the  hand  where  there  are  no 
oil  glands.  Painters  and  type  setters  are  often  made  sick 
by  getting  the  lead  from  paint  or  type  rubbed  into  the 
pores,  and  this  is  also  the  way  poison  from  poison  oak 
enters  the  system. 

Uses  of  the  Skin. — The  skin,  with  its  various  ap- 
pendages, has  many  uses: 

1.  It  is  a  protector  of  the  delicate  organs  beneath  by 
being  soft,  flexible,  and  elastic. 

2.  It  is  a  medium  of  touch,  as  it  holds  the  ends  of  the 
nerves  of  sensation. 

3.  It  is  an  organ  of  excretion  or  exhalation,  and  acts 
with  the  lungs  and  kidneys  in  carrying  off  great  quan- 
tities of  waste  material.     Its  excretion  is  perspiration. 

4.  It  is  an  organ  of  absorption,  taking  in  liquids  by 
means  of  its  pores. 

5.  It  is  a  cooler  of  the  body,  by  the  evaporation  of  per- 
spiration. 


THE  SKIN  AND  ITS  APPENDAGES. 


61 


ORGANS    OF   INTEGUMENT,    OR    SKIN. 

f  Nails. 


Cuticle,  or  Epidermis,  or  Scarf  Skin.  < 


Cutis  Vera,  or  Dermis  . 


Shaft. 
Root. 
Hair,   j  Bulb. 

Papilla. 

I  Sac.  or  follicle. 
Oil  glands. 
Pigment  layer. 
.  Perspiratory,  or  sweat  glands. 

Papillae. 
Nerves. 
Blood  vessels. 
Muscles. 
Connective  tissue. 


THOUGHT,  OR  OBSERVATION,  QUESTIONS. 

What  two  things  follow  if  scarf  skin  is  torn  off? 

How  does  serous  membrane  differ  from  mucous  membrane? 

If  the  cuticle  has  no  feeling,  how  do  we  feel  cold  things? 

How  do  cells  of  pigment  layer  differ  from  those  of  upper  layer  of 
cuticle  ? 

Is  there  any  tube  in  the  center  of  a  hair? 

In  what  position  does  a  hair  stand? 

Which  is  its  widest  part? 

Why  does  it  hurt  a  man  more  to  have  his  whiskers  pulled  than 
his  hair? 

Why  does  part  of  a  nail  look  pink  and  part  white? 

Name  three  characteristics  common  to  hair  and  nails. 

How  do  oil  and  sweat  glands  differ  in  shape?    Draw  them. 

Where  do  oil  glands  open? 

Can  you  see  the  opening  of  the  sweat  glands? 

Why  is  a  person  warmer  on  a  damp,  hot  day  than  on  a  dry,  hot 
day? 


62  PHYSIOLOGY. 

CHAPTER   5. 

FOOD    SYSTEM. 

Need  of  Food. — Every  day  a  well  person  has  to  eat 
his  usual  amount  of  food  or  become  faint  and  hungry. 
He  chews  up  meat,  bread,  potatoes,  and  pie,  and  they  dis- 
appear, and  there  is  no  way  to  tell  from  the  outside  what 
become's  of  them.  If  he  fails  to  get  enough,  or  eats  what  is 
not  suitable,  he  is  in  pain.  So  he  learns  from  experience 
that  some  things  harm  him,  some  are  poisonous,  and 
others  make  him  feel  strong  and  comfortable.  The  expe- 
rience of  many  people  for  many  centuries  has  taught 
most  sensible  persons  what  is  fit  and  what  unfit  to  eat, 
so  that  now  each  one  is  not  compelled  to  eat  and  suffer 
for  himself. 

Hunger. — Hunger  is  a  call,  or  demand,  for  food,  and 
it  means  that  acting  or  growing  tissue  has  become  wasted 
and  needs  material  for  renewing  itself.  All  the  sub- 
stances, except  air,  that  are  needed  to  make  bone,  muscle, 
brain,  and  all  other  tissues  of  the  body,  must  be  taken 
into  the  mouth  as  food  and  prepared  in  the  food  canal  for 
places  where  they  are  needed,  since  parts  are  always 
wearing  out  and  being  renewed. 

The  Alimentary  Canal. — The  food,  or  alimentary, 
canal  is  long  and  tubular,  with  many  twists  and  some 
dilations  and  with  some  important  digestive  organs 
attached  (Fig.  31).  The  stomach  is  merely  an  organ,  a 
dilation  of  the  general  canal,  where  part  of  the  food  is 
acted  upon  by  special  juices. 

After  leaving  the  mouth  the  food  canal  is  tube-like  and 
for  about  nine  inches  is  called  the  gullet;  then  it  widens 
and  becomes  pear-shaped  and  is  called  stomach;  then  it 
becomes  tube-like  again  and  very  much  twisted,  or  folded, 


FOOD  SYSTEM. 


63 


FIG.  31  (Copied}.  Diagram  of  greater  part  of  Alimentary  Canal.— 0. 
(Esophageal  or  cardiac  opening;  &  Stomach;  P.  Pylorus.  Intestines: 
d.  Duodenum;  j.  Jejunum;  i.  Ileum;  c.  Caecum;  a.  Worm-like  ap- 
pendage (.Vermiform  Appendix};  co.  Ascending,  transverse,  and  descend- 
ing Colon;  /.  Sigmoid  Flexure  of  Colon;  r.  Rectum; ^>  Direction 

of  Food. 

and  is  called  small  intestine;  then  the  tube  widens  and 
becomes  the  larger  intestine  (Fig.  31).  A  small  duct 
leads  from  the  liver  to  the  upper  part  of  the  smaller  intes- 
tine, and  another  from  the  pancreas  enters  near  the 
same  place. 

Organs  of  Digestion. — These — gullet,  stomach,  in- 
testines, liver,  and  pancreas — are  the  organs  of  digestion. 
Their  work  is  to  change  solid  food  into  liquids  that  are 
thin  enough  to  ooze  through  the  walls  of  different  parts 


64 


PHYSIOLOGY. 


of  the  food  canal.  These  liquids  that  contain  all  the 
nutritive  parts  of  the  food  we  eat,  enter  the  blood  vessels 
and  are  carried  all  over  the  body  to  renew  parts  that  are 
wearing  out. 

Digestive  Process. — Digestion  is  the  process  of 
changing  food  into  material  needed  for  growth  of  tissues. 
In  nearly  all  food  there  are  useless  parts,  and  these  are 
carried  from  the  body  as  waste  material  in  various  ways, 
by  the  skin,  the  lungs,  the  kidneys,  and  the  larger  intes- 
tines. Preparing  the  nutrient  liquid  is  a  long  process  of 
grinding,  mixing,  soaking,  and  straining,  and  in  doing 
this  different  organs  along  the  road  have  different  func- 
tions and  act  on  particular  parts  as  the  mass  of  food  is 
pushed  along  by  muscular  action. 

Lining  of  the  Ganal. — The  food  canal  begins  with  the 
lips.  The  delicate,  soft,  moist,  and  red  membrane  seen 
here  is  continued  as  lining  through  the  entire  length. 
It  is  mucous  membrane.  It  varies  in  character  in  differ- 
ent parts  of  the  canal.  On  the  tongue  it  is  rough  with 
little  projections;  in  the  stomach  it  is  thrown  in  folds  and 
is  full  of  cells  and  glands;  and  in  the  intestines  it  is  folded 
crosswise  and  has  numerous  patches  and  tufts  of  glands. 
The  folds  permit  a  great  deal  of  surface  to  be  packed  in 
a  small  space. 

Glands. — Glands  along  the  food  canal  are  numerous 
and  important,  and  will  be  described  with  the  larger 
organs  with  which  they  are  most  closely  connected. 
Glands  of  all  the  mucous  membrane  secrete  a  liquid  called 
mucus,  which  keeps  the  membrane  moist. 

Salivary  Glands. — In  health  the  mouth  is  always 
moist,  but  it  is  not  entirely  because  of  mucus.  When  a 
person  thinks  of  peaches,  or  some  juicy,  luscious  fruit  or 
food,  his  mouth  waters.  The  glands  pour  out  an  extra 


FOOD  SYSTEM. 


65 


supply  of  their  secretion.  The  secretion  is  called  saliva. 
It  is  frothy  and  white,  dissolves  such  kinds  of  food  as 
have  starch  in  them,  keeps  the  mouth  moist,  and  aids  in 
detecting  the  taste  of  substances. 


FIG.  32.  Salivary  Glands  (diagram). — 1.  Upper  Jaw;  2.  Tongue;  3. 
Sublingual  Gland;  4.  Submaxillary  Gland;  5.  Parotoid  Gland,  with 
Ducts. "  Dotted  line  shows  position  of  lower  jaw. 

The  saliva  is  made  by  three  sets  of  glands.  They  look 
something  like  bunches  of  grapes  (Fig.  32).  One  pair  is 
found  just  under  the  ears,  .and  extends  a  little  forward 
on  the  jaw  bone,  on  each  side  of  the  face.  The  second 
pair  is  just  under  the  angles  of  the  jaw  bone,  and  the 
third  pair  is  close  together,  just  under  the  front  part  of 
the  tongue. 

They  all  discharge  the  fluid  they  make  into  the  mouth 

5— P 


66 


PHYSIOLOGY. 


by  tiny  ducts.  The  opening  of  the  pair  under  the  tongue 
can  be  seen  just  back  of  the  lower  front  teeth,  by  lifting 
up  the  tongue.  The  liquid  can  be  seen  oozing  out. 

The  Tongue. — The  tongue  is  remarkable  for  the  short- 
ness of  its  muscular  fibres,  and  the  number  of  ways  they 
run.  This  gives  it  a  great  variety  of  motions.  It  is  an 
organ  of  taste  and  touch,  and  moves  the  food  about,  and 
helps  in  speaking.  The  tongue  is  not  absolutely  neces- 
sary for  speech,  although  it  is  an  important  helper.  Per- 
sons who  have  lost  their  tongues  by  disease  or  accident 
have  been  able  to  speak  many  words,  but  there  was  a 
loss  of  power  to  pronounce  t  and  d  sounds.  Can  you  tell 
why? 

Teeth. — Teeth  are  the  crushing  organs.  They  are 
sometimes  classified  with  bone,  but  they  are  really  like 
it  only  in  hardness  and  composition,  and  they  differ  in 
origin  and  structure.  Bones  originate  from  cartilage,  and 
teeth  from  mucous  membrane.  Fig.  28  shows  that  a 
tooth  grows  from  an  infolding  of  mucous  membrane  and 
a  papilla,  the  same  as  a  hair  (Fig.  24)  and  a  nail  (Fig.  27). 


Crown 


III. 


I.  II. 

PIG.  33.  Tooth  Sections.— I.  Section  of  Whole  Tooth  (natural  size): 
1.  True  Bone,  or  cement,  with  Canaliculi;  2.  Canal  for  Nerve,  and 
Blood  Vessel;  3.  Pulp  Cavity;  4.  Dentine;  5.  Enamel. 

II.  Section  of  Bone  and  Dentine,  very  greatly  magnified. 

III.  Section  of  Enamel  and  Dentine,  very  greatly  magnified. 


FOOD  SYSTEM.  67 

Structure. — Notice  the  hard  outside  of  your  teeth.  It 
is  very  hard,  harder  than  bone.  If  a  dog's  tooth  is  found, 
it  can  easily  be  broken,  showing  how  brittle  and  thin 
this  layer  is.  It  is  called  enamel.  Under  it  the  greater 
bulk  of  the  tooth  is  not  so  hard,  nor  so  white.  It  is  called 
dentine.  Around  the  root  of  the  tooth  there  is  a  thin  film 
of  bone,  called  cement  (Fig.  33,  I.  1).  The  microscope 
shows  that  tooth  structure  is  very  different  from  bone  ( Fig. 
33,  II.,  III. ) .  The  enamel  is  in  straight  up  and  down  rods, 
having  lines  running  across;  the  dentine  is  made  of  rather 
oblique,  wavy  little  tubes,  which  branch  as  they  approach 
the  enamel,  or  the  coat  of  bone,  while  the  coat  of  bone 
around  the  root,  like  all  bone,  is  made  up  of  little  lakes 
and  canals. 

Parts. — Every  tooth  has  three  parts:  the  crown  above 
the  gum,  the  root  that  fastens  in  the  socket  or  hollow 
of  the  jaw,  and  a  hollow  inside,  called  pulp  cavity  (Fig. 
33,  I.).  Sometimes  the  roots  are  called  fangs.  The 
socket  is  lined  with  mucous  membrane,  which  bleeds 
when  the  tooth  is  pulled  out.  The  pulp  cavity,  in  a  live 
tooth,  is  filled  with  a  grayish  pulp  made  of  nerves  and 
blood  vessels.  The  nerves  cause  a  tooth  to  ache,  or  hurt, 
when  pulled  or  when  it  is  decayed;  for  teeth,  like  hair, 
and  nails,  and  cuticle,  are  insensible,  and  the  hurt  is  in 
the  nerve  cavity,  or  the  gum  outside.  Nerves  and  blood 
vessels  enter  the  pulp  cavity  by  means  of  minute  open- 
ings in  the  roots  of  the  teeth  (Fig.  34). 

Incisors. — Notice  how  your  teeth  differ  in  size  and 
shape.  The  four  front  teeth  on  the  upper  and  lower  jaws 
are  flattened  and  sharp,  somewhat  like  a  chisel.  They 
are  called  incisors. 

Canines. — Just  back  of  each  of  the  last  incisors  there 
is  a  tooth  that  is  generally  longer  and  sharper  than  the 


1 


68  PHYSIOLOGY. 

others.  It  is  called  canine,  from  a  word  meaning  dog, 
because  dogs  have  these  teeth  remarkably  long  and  sharp. 
It  is  well  to  examine  the  teeth  of  a  dog  or  a  cat  to  find 
how  they  differ  from  ours.  Animals  that  have  these  teeth 
large  catch  and  tear  their  live  prey  with  them.  The 
canines  on  the  upper  jaw  are  called  "eye  teeth." 


FIG.  34.  Jaw  and  Teeth. — 1.  Artery ;  2.  Vein ;  3.  Nerve ;  4.  Foramen 
Nerves  and  Blood  Vessels;  5.  Incisor  Teeth;  6.  Canine  Teeth;  7. 
Bicuspid  Teeth;  8.  Molar  Teeth;  9.  Section  of  Tooth  (E.  Enamel,  D. 
Dentine,  B.  Bone,  P.  Pulp  Cavity) ;  10.  Second,  or  Permanent  Teeth. 

Bicuspids. — Just  back  of  the  canines  are  two  teeth 
on  each  half  jaw  that  sometimes  have  two  roots.  They 
are  called  bicuspids.  All  the  teeth  in  front  of  them  have 
a  single  root. 

Molars. — Back  of  the  bicuspids  there  are  three  broad, 
flat-crowned  teeth  that  have  two  or  three  fangs.  They 
are  the  grinders,  or  molars.  They  pulverize  the  food,  and 
with  the  aid  of  saliva,  make  it  into  a  pulpy  mass  easy 
to  swallow  and  digest.  The  last  molars  on  each  jaw 
are  called  "  wisdom  teeth."  They  are  the  last  to  come, 
sometimes  never  coming  through  the  gum,  and  often  are 
not  cut  till  the  twentieth  or  twenty-fifth  year. 

Two  Sets  of  Teeth. — There  are  two  sets  of  teeth. 
The  first  is  cut  in  babyhood,  and  lasts  till  the  sixth  or 


FOOD  SYSTEM.  69 

eighth  year,  and  is  called  the  milk  set.  It  numbers 
twenty.  The  other,  the  permanent  set,  begins  to  come 
about  the  sixth  year,  and  is  complete,  except  wisdom 
teeth,  by  the  twelfth  or  thirteenth  year,  and  lasts  a  vary- 
ing time.  It  numbers  thirty-two  teeth.  There  are  eight 
on  each  half  jaw  (Fig.  34). 


FIG.  35.  Section  of  Head.— 1.  Air  Cavities  in  Bone;  2.  Olfactory 
Bulb ;  3.  Nasal  Cavity  with  Turbinated  Bone ;  4.  Teeth ;  5.  Tongue ;  6. 
Hard  Palate ;  7.  Soft  Palate ;  8.  Epiglottis ;  9.  Vocal  Cords ;  10.  Wind- 

Eipe  (Trachea) ;  11.  Vertebras;  12.  Spinal  Cord;  13.  Medulla Oblongata, 
eginning  of  the  Spinal  Cord;  14.  Cerebellum  (cut);  15.  Dura  mater 
between   Hemispheres   of  Cerebrum;   16.  Corpus  Callosum,  holding 
Hemispheres  together;  17.  Gullet  ((Esophagus);  18.  Optic  Nerve. 

When  permanent  teeth  are  ready  to  come  they  grow 


70  PHYSIOLOGY. 

from  their  bulbs,  and  push  out  the  milk  teeth  (Fig.  34). 
Sometimes  the  milk  teeth,  whose  roots  are  absorbed,  loosen 
and  fall  out  easily,  but  generally  they  have  to  be  pulled 
out,  and  it  requires  some  courage  from  the  little  man  or 
woman  to  stand  up  and  have  the  loose  tooth  whisked 
out.  If  left  too  long  they  crowd  the  new  teeth  and  make 
them  grow  in  crooked. 

Action  of  Teeth. —  The  action  of  teeth  is  purely 
mechanical — the  breaking  up  of  food  so  it  can  be  easily 
dissolved.  A  mechanical  action  breaks  up,  but  does  not 
change  the  nature  of  a  substance.  Pounding  up  chalk  or 
limestone  is  a  mechanical  action.  The  saliva  has  a 
chemical  action  on  food.  Chemical  action  changes  the 
nature  of  compounds,  as  the  action  of  acid  on  limestone 
fragments  makes  another  kind  of  lime  compound. 


FIG.  36  (Copied).  Stomach  and  Duodenum,  showing  folds. — 1.  Gullet 
((Esophagus)',  2.  Cardiac  end  of  Stomach;  3.  Folds  (Rugx)-  4.  Intes- 
tinal Folds  ( Valvulx  Conniventes) ;  5.  Opening  for  Bile  and  Pancreatic 
Juice;  6.  Duodenum;  7.  Pylorus;  8.  Cardiac  Opening. 


FOOD  SYSTEM. 


71 


Motion  of  Jaws. — The  muscles  of  the  jaws  cause 
the  teeth  to  move  over  each  other  in  various  ways. 
Find  how  many  motions  your  jaw  can  make. 

The  action  of  teeth  is  called  chewing,  or  mastication. 

Gullet. — Food  gets  into  the  stomach  by  means  of  a 
tube  called  the  gullet.  It  is  back  of  the  windpipe  (Fig. 


15 


FIG.  37.  Cavities  and  Contents  of  Trunk. — 1.  Windpipe  (Trachea)', 
2.  Aorta;  3.  Lung  (Right);  4.  Ribs  and  Costal  Muscles ;  5.  Diaphragm; 
6.  Liver;  7.  Bile  Cyst;  8.  Worm-like  appendage  (Appendix  vermi- 
formis);  9.  Pleura  (Lung  Cover);  10.  Heart;  11.  Pericardium;  12.  Left 
Lung  (2  lobes);  13.  Stomach;  14.  Spleen;  15.  Large  Intestine;  16. 
Small  Intestine. 

35).     It  has  three  coats.     It  is  lined  with  mucous  mem- 
brane, has  a  coat  of  muscular  tissue,  and  an  outer  one  of 


72 


PHYSIOLOGY. 


serous  membrane.  (See  Glossary  for  Serous  Membrane.) 
Its  muscular  fibres  are  arranged  in  rings  running  around, 
and  in  lines  running  up  and  down  the  tube,  and  when 
they  act  together  they  catch  a  lump  of  food  and  squeeze 
it  along  in  a  peculiar,  squirming  way,  giving  it  a  worm- 
like  motion  called  vermicular.  All  the  gullet  does  is  to 
pass  the  food  along.  The  process  is  called  swallowing. 

Stomach. — The  stomach  is  the  largest  dilation  of  the 
food  canal.  Its  larger  end  is  toward  the  left  side,  and 
because  this  is  nearer  the  heart  its  opening  is  called  the 
cardiac  opening  (Fig.  36).  The  other  orifice,  near  the 
small  intestine,  is  called  pylorus,  a  gateway. 


FIG.  38.  Lining  and  Wall  of  Stomach.— 1.  Gland  layer;  2.  Bloodves- 
sel and  muscle  layer,  showing  cut  blood  vessels  and  bundles  of 
muscle  fibres  (3)  cut  across ;  4.  Serous  layer. 

The  stomach  is  tucked  up  closely  under  the  diaphragm, 
and  extends  more  than  half  way  across  the  front  of  the 
body  (Fig.  37).  It  has  folds  running  lengthwise  (Fig. 
36).  Like  the  gullet,  it  has  three  coats.  The  fibres  of 
the  muscular  coat  are  arranged  lengthwise,  crosswise,  and 
slanting,  and  they  pull  in  all  directions.  When  they 


FOOD  SYSTEM. 


73 


contract,  they  press  the  food  around  against  all  parts  of 
the  walls,  giving  it  a  motion  called  peristaltic. 

Glands  and  Juices  of  the  Stomach. — The  walls 
of  the  stomach  are  full  of  glands,  which  make  gastric 
juice,  and  by  the  motion  the  food  is  brought  in  contact 
with  it.  The  soft  mucous  membrane  has  a  tufted  look 
under  the  microscope  (Fig.  38),  but  is  delicate,  and  not 
unlike  pink  velvet  to  look  at  with  the  naked  eye.  Part 
of  the  food  that  is  taken  as  liquid,  or  that  is  made  liquid 
by  saliva  and  gastric  juice,  soaks  through  this  membrane, 
and  enters  the  blood  vessels  that  pass  through  the  mus- 
cular coat. 

The  glands  that  make  gastric  juice  do  not  look  like  the 

salivary  glands  (Fig. 
39).  The  gastric  juice 
is  the  most  important 
2  dissolver  in  the  body. 
It  is  the  second  one 
found  in  the  alimen- 
tary canal,  the  saliva 
being  first.  It  is  acid, 
and  also  has  a  sub- 
stance in  it  called 
pepsin,  which  dis- 
solves such  food  as 
white  of  egg  and  lean 
meat. 


r 
1 


Absorption  by 
the  Stomach. — 
When  the  food  enters 
the  stomach,  it  is  a 
pulpy  mass.  Drinks 
like  water,  tea,  beer,  wine,  and  dissolved  sugars,  seep 
through  the  walls  of  the  stomach,  leaving  the  solid  foods 


FIG.  39.  Gastric  Follicles  which  con- 
tain Gastric  Glands.— 1.  Cut  Tubes  show- 
ing cellular  lining;  2.  Uncut  Tubes,  or 
Follicles. 


74 


PHYSIOLOGY. 


to  be  dissolved.  The  muscles  squeeze  out  the  gastric  juice 
till  it  stands  upon  the  walls  like  drops  of  dew.  It  sat- 
urates the  food.  The  layer  of  food  that  is  dissolved  by 
this  juice  strains  through  the  stomach  walls;  and  the 
undigested  remainder,  a  half  liquid  mass,  comes  to  the 
pylorus.  It  is  now  called  chyme. 

Then  the  muscles  that  close  the  pylorus  relax,  and  the 
chyme  is  pushed  onward.  If  a  button,  bone,  or  other  hard 
substance  be  swallowed,  it  is  pressed  around  with  the 
food  till  it  reaches  the  pylorus.  It  tries  to  pass  through, 
but  is  turned  back  to  get  another  soaking.  It  goes 
around  again,  the  gastric  juice  trying  to  turn  it  into 
pulp,  till,  in  despair,  it  is  allowed  to  squeeze  through  the 
pylorus  into  the  intestine;  but  not  until  some  time  after 
the  good  material  has  passed  through. 

Small  Intestine. — The  smaller  intestine  comes  next 
to  the  stomach.  It  is  considerably  smaller  than  the 
large  intestine  (Figs.  31,  37).  It  begins  on  the  right  side, 

and  goes  twisting 
across  the  body.  Both 
intestines  are  long; 
together  they  measure 
about  twenty-five  feet, 
and  have  to  be  very 
much  folded,  in  order 
to  fit  in  the  space  of 
the  abdomen.  The 
small  intestine  has 
three  coats.  The  inner  one  is  in  folds,  crosswise  ( Fig.  40) . 

Glands  and  Juices  of  Small  Intestines.— The 
glands  in  the  mucous  membrane  are  numerous,  and  have 
a  greater  variety  of  function  than  those  of  any  other  part 
of  the  food  canal.  Two  very  important  juices  enter  it 
near  the  stomach  (Fig.  36).  One  comes  from  the  liver, 


FIG.  40  (Copied}.  Section  of  Small  In- 
testines.— Showing  folds  in  lining  (Val- 
vulae  Conniventes). 


FOOD  SYSTEM.  75 

and  is  called  bile;  the  other  comes  from  the  pancreas, 
and  is  called  pancreatic  juice.  They  act  on  the  fats  that 
have  passed  unchanged  by  the  other  juices,  dividing  them 
into  small  particles,  and  forming  a  milky  fluid  called 
chyle.  The  chyle  oozes  through  the  walls  of  the  intestines. 

Pancreas. — The  pancreas  is  a  flat,  long  gland,  just 
back  of  the  stomach.  Its  color  is  ashy  pink.  The  juice 
it  makes  has  three  uses — it  changes  sugar,  egg  and  meat, 
and  fats  so  that  they  can  all  enter  the  circulation. 

Liver. — The  liver  is  the  largest  gland  in  the  body. 
Fig.  37  shows  its  position  on  the  right  side,  just  under  the 
diaphragm.  It  laps  over  part  of  the  stomach.  Beef 
liver  in  the  shops  shows  its  color,  shape,  and  structure. 
It  is  reddish  brown,  thin  on  the  edges,  and  breaks  in 
angular  pieces.  It  is  divided  by  deep  fissures  into  lobes 
(Fig.  37).  Outside  it  is  smooth  and  shiny,  because  cov- 
ered with  a  thin  serous  membrane,  and  has  a  mottled 
look  that  is  caused  by  its  being  made  up  of  small  parts 
called  lobules  (Fig.  55).  The  lobules  are  formed  of 
microscopic  parts  called  liver  cells.  The  cells  are  many 
sided.  How  they  look  in  ordinary  position,  when  crowded 
together,  is  shown  in  3,  Fig.  3. 

Veins,  arteries,  and  blood  and  bile  capillaries  run  in  all 
directions  through  the  substance  of  each  lobule.  Blood 
vessels  carry  in  the  blood  to  renew  the  lobules  and  the 
blood  that  needs  changing,  and  carry  out  worn-out  parts, 
and  reorganized  blood;  and  the  bile  capillaries  carry  the 
bile  that  has  been  formed. 

Function  of  Liver. — It  used  to  be  thought  that  the 
only  use  of  the  liver  was  to  make  bile,  but  now  it  is  sup- 
posed to  be  a  very  important  organ  for  preparing  blood, 
because  nearly  all  the  blood  from  the  stomach  and  intes- 
tines goes  through  it  before  entering  the  general  circula- 
tion of  the  body. 


76 


PHYSIOLOGY. 


It  not  only  secretes  bile,  a  new  material  partly  useful 
and  partly  waste,  but  it  also  changes  the  blood  that 
passes  through  it,  and  it  makes  a  new  substance  called 
glycogen.  Glycogen.  is  something  like  starch,  and  is  stored 
up  in  the  liver  till  it  is  needed  to  produce  heat  in  the 
body. 

Bile. — The  bile  is  secreted  from  the  blood  in  the  liver 
cells,  and  collects  around  the  cells,  and  then  it  enters  the 
bile  capillaries  and  flows  out  of  the  liver  to  a  little  bag 
called  bile  cyst  (7,  Fig.  37).  Here  it  is  stored  up.  Fig. 
41  is  a  diagram  showing  how  it  enters  bile  capillaries, 
and  the  direction  it  takes.  It  flows  outward  from  the 
center  of  the  lobule,  while  the  blood  flows  toward  the 
center.  The  central  part  of  a  lobule  is  a  vein  which  con- 


FIG.  41.  Diagram  of  part  of  Liver  Circulation.— 1.  Blood  capillary 
(Blood  flows  toward  center  of  Lobule);  2.  Bile  capillary  (Bile  flows 
toward  outside  of  Lobule);  3.  Space  between  Liver  cells;  4.  Liver 
cells;  5.  Nucleus  of  cell.  (Showing  that  cells  secrete  bile  from  blood 
which  is  on  its  way  to  Vena  Cava  Ascending  via  intralobular  vein. 
Bile  first  is  between  cells,  then  is  collected  by  bile  capillaries  around 
cells  and  carried  away  from  lobule  to  Bile  Cyst.) 

nects  with  veins  of  other  lobules,  and  finally  enters  the 
large  vein  that  ascends  to  the  heart. 


FOOD  SYSTEM. 


77 


Bile  is  a  golden  brown,  thickish  liquid.  It  may  be  con- 
sidered a  secretion  and  an  excretion.  It  is  as  an  excre- 
tion that  it  has  some  action  on  the  food.  One  use  is  to 
help  break  up  fats,  another  to  stimulate  secretion  of  intes- 
tinal glands,  and  another  to  prevent  injurious  fermenta- 
tions in  the  food. 

Functions  of  Intestinal  Glands. — Besides  bile  and 
pancreatic  juice,  there  are  numerous  digestive  juices 
along  the  smaller  intestines.  They  are  not  as  well  under- 
stood as  the  others.  The  intestinal  glands  secrete  juices 
of  such  different  kinds,  that  any  food  that  has  escaped 
digestion  in  the  upper  part  of  the  canal  meets  its  dis- 
solver  here. 

Suppose  a   person    has   swallowed  starchy  food,  like 


FIG.  42.  Section  of  Intestine  (of  Bear)..— a.  Epithelium;  b.  Blood 
Vessels ;  c.  Vein ;  d.  Artery,  connected  by  Capillaries ;  b.  Lacteal ;  e.  Cut 
Blood  Vessel;  /.  Muscular  Coat;  1,  2,  3.  Cut  Villi;  4.  Uncut  Villus. 

potato,  only  half  chewed,  and  the  saliva  was  not  able  to 
penetrate  it;  or  that  meat,  or  eggs,  were  eaten  too  rapidly 
and  the  stomach  was  overcrowded  and  gastric  juice  could 
not  soak  in.  Then  the  mass  is  squeezed  through  the  pylo- 
rus, not  as  chyme,  but  as  lumps  of  food;  the  intestinal 
juices  pour  out  and  slowly  dissolve  the  food  as  it  passes 
along. 


78-  PHYSIOLOGY. 

This  work  can  be  done  to  a  limited  extent,  but  the 
practice  of  bolting  food  in  a  half  chewed  condition  throws 
too  much  work  on  these  glands  and  causes  disease,  for 
food  undigested  does  no  good  and  much  harm. 

Villi. — Chyle,  which  is  formed  by  the  action  of  bile 
and  pancreatic  juice  on  chyme,  is  ready  to  go  through 
the  walls.  It  is  thin,  and  has  a  milky  look. 


FIG.  43.  Diagram  of  a  Villus. — 1.  Cells  of  Mucous  Coat  of  Intestine; 
2.  Vein ;  3.  Lacteal ;  4.  Artery. 

But  it  does  not  get  into  the  circulation  like  food  that 
soaks  through  the  stomach  walls.  The  mucous  mem- 
brane of  the  intestines  is  so  modified,  as  to  look  some- 
thing like  velvet.  The  microscope  shows  that  it  contains 
an  immense  number  of  tiny  tubes  (Fig.  42).  These 
tubes  extend  into  the  liquid  food  like  little  fingers,  and 
the  chyle  soaks  through  their  delicate  walls.  Each  tube 
is  called  a  villus  (plural,  villi).  A  villus  contains  a  capil- 
lary vein  and  artery,  and  a  minute  vessel  called  a  lacteal 


FOOD  SYSTEM.  79 

(Fig.  43).  The  part  of  the  food  that  enters  the  blood 
vessels  of  the  villus  goes  to  a  larger  vein,  and  then  to 
the  liver  (Fig.  53).  The  chyle  oozes  into  the  lacteal. 

The  veins  take  up  the  same  materials  that  the  stomach 
veins  do.  But  when  the  two  food  substances  are  sepa- 
rated in  a  villus,  one  going  into  a  vein,  and  the  other  into 
a  lacteal,  they  never  see  anything  more  of  each  other 
unless  they  happen  to  meet  in  the  general  circulation. 

The  fatty  food  that  entered  the  lacteal  of  the  villus 
passes  to  a  larger  vessel,  and  then  through  glands  in  a 
serous  membrane  that  holds  the  intestine  (Fig.  44),  then 
up  to  a  tube  called  the  thoracic  duct,  that  leads  to  a  vein 
on  the  left  side  of  the  neck. 

Thoracic  Duct. — The  thoracic  duct  is  important, 
because  it  takes  up  all  the  fatty  food.  It  is  about  the 
size  of  a  goose  quill.  Where  all  the  lacteals  enter,  it  is 
widened  (33,  Fig.  53). 

Absorption. — The  power  of  taking  up  liquid  food  by 
veins  and  lacteals  is  called  absorption.  There  are  no  visi- 
ble openings  in  these  vessels.  Certain  organic  substances 
let  liquids  freely  pass  through  them.  If  a  bladder  is 
filled  with  colored  liquid,  and  hung  in  a  jar  of  pure 
water,  the  colorless  water  gets  into  the  colored  liquor, 
and  the  colored  liquid  gets  out.  This  changing  of  places 
is  called  osmose.  Liquids  mix  if  separated  by  such  sub- 
stances, and  so  do  gases,  and  the  process  is  the  same. 

Kinds  of  Digestion. — In  the  small  intestine  probably 
all  the  work  of  digestion  is  completed.  The  process  of 
dissolving  food  by  the  juices  of  the  mouth  is  called 
salivary  digestion,  dissolving  by  gastric  juice  is  called 
gastric  digestion,  and  by  intestinal  juices  intestinal  diges- 
tion. 

The  Large  Intestine. — The  large  intestine  is  wider 


80 


PHYSIOLOGY. 


than  the  small  one,  and  it  is 
about  five  feet  long.  It  is 
folded  up  over  the  convolu- 
tions of  the  smaller  (Fig.  37). 
Through  it  husks  and  other 
non-nutritive  parts  of  the  food 
pass  from  the  system.  The 
intestines  are  covered  with 
serous  membrane,  which  al- 
lows them  to  move  freely  on 
each  other. 

Vermiform  Append- 
age.— Just  after  the  large  in- 
testine begins,  there  is  a  queer 
little  arrangement.  It  is  a 
little  tube,  coiled  up  like  a 
worm,  on  the  right  side  (8, 

FIG.  44  (Copied).  Portion  of    Fig.    37),    and   is   called   the 

vermiform  appendage.  It  does 
not  seem  to  be  of  any  use,  but 
it  is  liable  to  make  a  great 
deal  of  mischief.  As  materials  pass  by  its  mouth,  a  part 
is  apt  to  be  pressed  into  this  tube.  If  it  is  soft,  it  is 
pressed  out  again;  but  if  it  is  hard,  like  cherry  or  plum 
pits,  there  may  be  trouble.  The  hard  particles  get  packed 
in,  cannot  be  driven  out,  and  they  cause  inflammation, 
and  if  not  removed,  cause  death.  In  one  case  a  child  ate 
chestnut  leaves,  and  the  harsh  fibres  became  packed  in 
this  little  tube,  and  killed  him.  In  another  death  was 
caused  by  the  tube  getting  pressed  full  of  chewing  gum. 
The  importance  of  food  is  seen  in  the  various  and 
complicated  machines  engaged  in  its  digestion,  and 
these  are  so  closely  connected  with  other  systems,  that 
it  is  easy  to  understand  how  bad  food  can  make  the 
whole  body  sick. 


Small  Intestine  and  Mesen- 
tery.— 1.  Intestine;  2.  Mesen- 
tery (Serous  Membrane);  3. 
Lacteal, or  Lymphatic,  Glands ; 
4.  Lacteal  Vessels. 


FOOD  SYSTEM. 


81 


ORGANS    AND    JUICES    OF    DIGESTION. 


Mouth  for  Mastication,  or  Chew- 
ing, and  Salivary  Digestion. 


Teeth. 


Tongue. 

f  Incisors. 

Canines. 

Bicuspids. 
[  Molars. 

f  Parotid. 
Salivary  Glands.  \  Sublingual. 

[  Submaxillary. 

Saliva,  contains  Ptyalin  (a  fer- 
ment). 
Taste  Corpuscles. 


Pharynx  and  (Esophagus  for  Swal- 
lowing, or  Deglutition.  Stomach  for 
Gastric  Digestion  and  Absorption. 


Liver*. — Bile  cyst  and  Bile. 


Openings. 


f  Cardiac. 


Intestines       for 
Intestinal   Di- 
gestion       and  j  ^ 
Absorption. 


f  Small.   •{  Duodenum,  Jeju- 

num, Ileum.     . 

o> 


L  Pyloric. 
Glands. 
Veins. 
Folds. 

Gastric  Juice,  contains  Pep- 
sin (a  ferment). 


Pancreas. 

Pancreatic  Juice, 
contains    Pan- 
creatin  (a   fer- 
ment). 
Villi. 
Intestinal  glands  and 

juices. 
Lacteals. 


Large. 


Caecum.  <{  Appendix  vermiformis. 

f  Ascending. 
Colon.  \  Transverse. 

[  Descending. 
Rectum. 


THOUGHT,  OR  OBSERVATION,  QUESTIONS. 

Why  is  food  moved  around  in  the  stomach? 
Show,  by  drawing,  the  difference  between  dentine  and  enamel. 
Why  should  children  ever  have  milk  teeth  extracted  ? 
Why  should  they  never  have  them,  filled? 
6-P 


82  PHYSIOLOGY. 

How  do  salivary  glands  differ  from  sweat  glands? 

How  does  the  tongue  serve  to  protect  against  bad  food  ? 

Draw  a  gastric,  a  salivary,  an  oil,  a  perspiratory  gland,  and  the 
liver,  side  by  side,  and  compare  them. 

How  does  gastric  juice  get  into  the  stomach? 

What  is  it  made  from? 

What  is  the  use  of  the  great  number  of  veins  and  capillaries  in 
the  liver? 

If  fatty  foods  go  to  thoracic  duct,  how  does  liver  get  its  fatty 
material? 


CIRCULATION.  83 

CHAPTER  6. 

CIRCULATION. 

The  heart,  whose  beating  can  be  felt  on  the  left  side, 
the  pulse  throbbing  at  the  temples  and  wrists,  the  veins 
that  look  on  the  surface  of  the  skin  like  bluish  cords,  and 
the  blood  that  flows  from  a  cut,  are  all  intimately  con- 
nected. Similar  blood  in  like  veins  runs  through  nearly 
all  tissues  of  the  body.  Its  motion  is  called  circulation. 
The  heart  drives  it  along. 

As  the  tissues  receive  all  their  material  from  the  blood, 
it  is  evident  that  the  blood  must  contain  all  the  materials 
of  which  the  tissues  are  made.  It  also  carries  waste  mat- 
ter. All  that  is  in  the  blood  comes  in  the  first  place  from 
air  or  food. 

It  is  easy  to  understand  that  blood  is  not  always  the 
same.  In  one  place  it  is  full  of  new  material  from  the 
food;  in  another  it  has  more  air;  and  in  another  it  has 
an  excess  of  waste  material.  It  varies  in  the  different 
things  it  contains,  and  these  make  it  vary  in  color. 

Corpuscles. — If  blood  is  placed  under  a  microscope 
it  is  found  to  be  made  of  two  parts — a  colorless  liquid 
and  a  multitude  of  little  disc-like  cells.  These  cells  are 
called  corpuscles.  They  are  yellowish,  and  when  crowded 
together  give  the  blood  its  bright  red  color.  Not  all  cor- 
puscles are  colored.  There  are  three  kinds:  large  color- 
less; medium  sized  colored;  and  small  colorless  corpuscles. 
The  large  ones  are  granular,  few  in  number,  and  are  called 
white  or  colorless  corpuscles.  The  medium  sized  ones 
are  most  abundant  and  are  called  red  or  colored  corpus- 
cles. The  small  ones  are  flattened  discs,  more  common 
than  the  colorless  ones,  and  they  are  called  blood  plates 
or  third  blood  corpuscles.  The  function  of  both  the 


84 


PHYSIOLOGY. 


small  and  the  large  colorless  cells  has  not  been  satisfac- 
torily shown,  but  it  is  supposed  that  the  larger  ones 
sometimes  build  tissue  and  also  break  up  to  form  red 
cells,  and  that  the  smaller  ones  help  in  the  coagulation 
of  blood.  The  colored  corpuscles  are  hollowed  out  on 
each  side  (2,  Fig.  3).  When  exposed  to  the  air,  they  have 
a  queer  habit  of  packing  together  in  long  rows  (Fig.  45). 
Sometimes,  under  one's  eye  they  move  about,  and  when 
they  come  to  a  narrow  place  they  squeeze  through,  chang- 
ing their  shapes  (4,  Fig.  45).  This  shows  that  they 
are  flexible.  When  they  stay  quite  a  number  of  minutes 


FIG.  45.  Blood  Corpuscles. — 1.  Normal  Shape  (colorless  and  colored 
Corpuscle) ;  2,  3.  Corpuscles  crowded ;  4.  Crowding  through  narrow 
space ;  5.  Piles  of  colored  Corpuscles ;  6.  Colored  Corpuscles  stellated 
from  evaporation. 

in  the  air  they  begin  to  dry,  and  look  like  little  burrs 
(6,  Fig.  45). 

If  the  foot  of  a  live  frog  is  put  under  the  glass,  the  cor- 
puscles, which  are  larger  than  ours,  can  be  seen  through 
the  thin  web  fleeting  along  rapidly,  passing  each  other  in 
lines,  and  changing  shape. 


CIRCULATION.  85 

The  blood  cells  are  among  the  most  important  of  small 
bodies.  Their  work  is  to  carry  oxygen.  Oxygen  is  a  gas 
that  cannot  be  seen,  but  it  is  absolutely  necessary  to  ani- 
mal life.  This  gas  is  taken  in  by  the  lungs  every  time 
we  breathe  in  pure  air.  Multitudes  of  corpuscles  take  it 
up  in  the  lungs,  and  away  the  fleet  of  tiny  red  boats  goes 
sailing  through  the  system,  leaving,  here  and  there,  the 
oxygen  wherever  it  is  needed,  till  they  are  all  unloaded. 
Then  the  corpuscles  either  go  to  pieces  in  the  stream,  or 
drift  off  to  some  place  where  they  are  renewed  or  broken 
up,  and  all  the  good  material  in  them  is  taken  for  other 
purposes. 

Plasma. — The  fluid  of  the  blood  is  called  plasma.  It 
contains  a  great  deal  of  water,  is  rich  in  food  products, 
and  carries  waste  material  and  different  gases.  One 
part  of  it  is  something  like  the  white  of  an  egg  and 
hardens  when  exposed  to  the  air.  When  in  this  stiff, 
jelly-like  condition  it  is  called  clot,  and  the  hardening  is 
called  coagulation. 

This  power  to  harden,  or  coagulate,  is  of  great  use,  for 
when  a  blood  vessel  is  cut,  the  blood,  exposed  to  air,  soon 
hardens  and  plugs  up  the  opening,  and  thus  prevents 
serious  bleeding. 

Capillaries. — Blood  flows  through  different  kinds  of 
vessels.  The  smallest  tubes  are  microscopic,  and  are 
called  capillaries.  Their  walls  are  so  thin  that  the  blood 
oozes  through  and  irrigates  the  surrounding  tissues. 
They  penetrate  nearly  all  tissues,  and  in  them  the  most 
important  changes  take  place.  They  interlace  and  form 
a  fine  network. 

Capillaries  are  not  merely  smaller  sized  veins  or  arte- 
ries, but  they  differ  in  having  their  walls  extremely  thin, 
and  in  having  fewer  coats.  They  connect  veins  with 
arteries  (Fig.  46).  If  one  capillary  of  the  network  gets 


86 


PHYSIOLOGY. 


injured,  the  blood  takes  a  new  course  through  the  near- 
est capillaries. 

Arteries  and  Veins.— The  two  other  kinds  of  blood 
vessels — arteries  and  veins — differ  essentially.  Near  the 
capillaries  they  are  very  small  and  much  alike,  but  farther 
away  they  are  enlarged.  There  are  six  important  dif- 
ferences: 

ARTERIES  VEINS 


Carry  blood  from  the  heart. 

Do  not  have  valves. 

Have  stiff  walls  that  stay  open 

when  empty. 
Have  elastic  walls. 


Carry  blood  to  the  heart. 

Have  valves. 

Have  soft  walls  that  collapse 

when  empty. 
Have   almost   no   elasticity  to 

walls. 

Are  generally  smaller. 
Generally  carry  blue  blood. 


Are  generally  larger. 
Generally  carry  red  blood. 

(Exceptions:  The  pulmonary  arteries  carry  blue  blood  to  the 
lungs  and  the  pulmonary  veins  carry  red  blood  from  the  lungs.) 


Veins  begin  as  fine 
tubes  at  the  capillaries, 
and  multitudes  of  them 
unite,  forming  larger 
and  larger  tubes,  till 
they  enter  the  heart  as 
two  large  trunks  from 
the  body  and  four  large 
tubes  from  the  lungs. 

Arteries  begin  at  the 
heart  as  two  large  tubes, 
one  going  to  the  lungs 
and  one  to  the  rest  of 
the  body,  and  these 
branch  and  rebranch 
till  they  are  fine  tubes 
and  then  they  change  to  capillaries. 


FIG.    46    (Copied).    Capillary 
work. — a.  Artery;  b.  Vein. 


Net- 


CIRCULATION. 


87 


FIG.  47. — 1.  Vein  with  Valves ;  2.  Artery,  cut  open ;  3.  Lymphatic  Ves- 
sel, outside;  4.  Lymphatic  Vessel,  inside,  showing  valves;  ^-Di- 
rection of  blood. 

Valves  of  Veins. — The  valves  of  the  veins  are  a  kind 
of  little  pocket  of  thin  membrane.  When  the  blood  flows, 
in  an  ordinary  manner  they  stick  tightly  to  the  walls, 
but  if  it  tries  to  flow  backward  to  the  capillaries  they 
instantly  fill  up  and  shut  up  the  passage  way. 

Motion  of  Blood. — The  blood  does  not  move  the 
same  in  all  vessels.  In  arteries  it  goes  with  a  jerk. 
This  means  that  when  an  artery  is  full  the  heart  pushes 
in  some  more  blood  with  a  quick  pressure.  The  elastic 
walls  yield,  pass  the  extra  quantity  on,  and  relax,  and 
so  on  through  its  entire  length,  thus  making  a  kind  of 
wave  motion.  Some  of  the  impulse  is  lost  as  the  artery 
divides,  and  finally  in  the  intricate  capillaries  there  is  a 
smooth  flow.  It  also  flows  smoothly  in  the  veins.  From 
this  difference  of  motion  it  is  easy  to  tell  whether  an 
artery  or  a  vein  is  cut,  for  blood  spurts  in  jets  from  an 
artery  and  flows  smoothly  from  a  vein. 

The  Pulse. — The  beating  of  the  pulse  is  merely  the 
motion  of  blood  through  an  artery  near  the  surface. 
The  doctor  counts  the  pulse-beat  to  find  the  condition  of 


88 


PHYSIOLOGY. 


R 


his  patient,  be- 
cause the  heart 
and  circulation 
are  affected  by 
the  diseases  of 
all  the  other  sys- 
tems. The  'beat 
is  slower  in 
grown  people, 
and  during  sleep. 
For  a  grown  per- 
son it  is  from 
seventy-five  to 
eighty-five  throbs 
a  minute. 

The   Heart.— 

The  heart  is  the 
chief  organ  of  cir- 
culation. It  has 
a  serous  mem- 
brane around  it, 
called  the  heart 
cover,  or  heart 
sac  (pericardium) 
(Figs.  48,  50).  It 
is  a  single  muscle, 
is  hollow,  somewhat  cone-shaped,  and  is  situated  in  the 
center  of  the  chest,  between  the  lungs,  with  the  small  end 
turned  to  the  left  side,  and  is  free  to  move  (Fig.  37). 
Heart  muscle  is  involuntary  (Fig.  22).  The  muscular 
fibres  run  in  many  directions  and  are  interlaced  in  an 
exceedingly  intricate  manner. 

Auricles  and  Ventricles. — The  heart  is  divided  into 
four  unequal   hollows,  or   chambers   (Fig.  49).     These 


FIG.  48.  Outside  of  Heart.— 1.  Auricles ; 
2.  Ventricles ;  3.  Heart  Sac  (Serous  Mem- 
brane); 4.  Aorta;  5.  Ascending  Vena  Cava; 
6.  Descending  Vena  Cava;  7.  Pulmonary 
Artery ;  R.  Right ;  L.  Left. 


CIRCULATION. 


89 


Aorta 


chambers     are 
nicely  shown  in 
a   beefs  heart. 
The  two  upper 
ones  are  called 
auricles,  from  a 
word    meaning 
ears,      because 
on  the   outside 
of    these   parts 
there  are  flaps 
that  look  some- 
thing   like   dog's 
ears      (Fig.      48). 
The  lower  chambers 
are  called  ventricles. 
Each    auricle     opens 
into  the  ventricle  be- 
low    it,    but    has    no 

FIG.  49.    Diagram  of  Chambers  and  opening  between  it  and 

Openings  of    the    Heart.— Blood  from  ,-.  n+i>p1.        onrinlA 

veins  of  body  enters  RA  at  1  and  leaves  tne        otner        auricle. 

R  V  for  lungs  at  2.    Blood  from  veins  of  Neither    do    the     ven- 
lungs  enters  LA  at  3  and  leaves  LVai. 

4  for  all  parts  of  the  body  except  the  tricles    connect, 
lungs.     W.  Walls  of  the  Heart. 

Valves. — The  openings  into  the  ventricles  are  guarded 
by  strong,  thin  membranes,  called  valves,  which  are  tubu- 
lar when  filled  with  blood.  They  form  a  kind  of  live 
door  (4,  11,  Fig.  50). 

The  valves  between  the  auricles  and  ventricles  are  of 
thin,  tough  membrane,  and  would  be  driven  through  into 
the  auricles  by  the  pressure  of  blood,  like  an  umbrella 
turned  inside  out,  were  they  not  held  in  position  by  cord- 
like  tissue.  These  cords  can  be  seen  in  14,  Figx»iOTv$U 

Beating  of  the  Heart. — When  the  blood  flows  into 
the  two  auricles,  from  the  general  circulation,  and  from 


90 


PHYSIOLOGY. 


the  lungs,  and  fills  them  up,  the  auricles  squeeze  together; 
the  doors  or  valves  are  forced  open,  and  the  blood  is 
pushed  down  into  the  ventricles.  Then  the  auricles  relax. 


13 


FIG.  50.  Heart  cut  open. — 1.  Descending  Vena  Cava ;  2.  Right  Auri- 
cle ;  3.  Ascending  Vena  Cava ;  4.  Tricuspid  Valve ;  5.  Right  Ventricle ; 
6.  Aorta ;  7.  Pulmonary  Artery ;  8.  Pulmonary  Veins ;  9.  Left  Auricle ; 
10.  Semilunar  Valves;  11.  Mitral,  or  Bicuspfd,  Valve;  12.  Left  Ven- 
tricle; 13.  Heart  Sac  (Pericardium),  (Serous  Membrane);  14.  Cords 
holding  the  valves  in  position. 

The  ventricles  quickly  contract,  and  give  the  blood  a 
push.  It  cannot  go  back  to  the  auricles,  for  the  doors  are 
tightly  closed,  so  it  rushes  up  through  the  large  arteries 
(Fig.  49),  one  called  pulmonary  artery,  going  to  the  lungs, 
and  the  other,  called  aorta,  going  to  other  parts  of  the 
body. 


CIRCULATION. 


91 


10 


3  — 


18 


Divisions  of  Heart. 


Blood  Vessels 
hind  Heart. 
Course  of  Blood 


be- 


FIG.  51.  Diagram  of  Pul- 
monary and  Systemic  Cir- 
culation.— 1.  Right  Carotid 
Vein ;  2.  Right  Carotid  Ar- 
tery ;    3.  Vena     Cava    De- 
scendens;    4.  Branches    of 
Right    Pulmonary  Artery 
(blue     blood    shaded,    red 
blood  unshaded) ;  5.  Aorta ; 
6.   Right    Auricle;    7. 
Lung;  8.  Right  Ven- 
tricle; 9.  Ascend- 
ing Vena  Cava ;  10. 
Left  Carotid  Artery ; 

11.  Vein  of  Left  Arm ; 

12.  Artery  of  Left  Arm  (Subclavian); 

13.  Pulmonary  Artery ;  14.  Three  "of  the  four  Pulmonary  Veins ;  15. 
Left  Auricle ;  16.  Lung ;  17.  Left  Ventricle ;  18.  Descending.  Aorta. 


92  PHYSIOLOGY. 

To  keep  the  blood  from  going  back  to  the  ventricles 
when  they  in  turn  relax,  there  are  three  little  pocket 
valves  (10,  Fig.  50,  shows  two  of  them)  at  the  opening  of 
the  large  pulmonary  artery  and  of  the  aorta.  So  the 
blood  is  just  pushed  right  along  through  the  arteries. 

This  contraction  and  expansion  of  the  heart  muscle 
causes  the  free  end  of  the  heart  to  strike  against  the  side 
of  the  chest,  and  that  is  called  the  beating  of  the  heart. 
The  heart  muscle,  which  seems  ceaseless  in  its  action, 
catches  its  rest  spells  between  its  times  of  contraction. 

The  Circulation  of  the  Blood. — The  passage  of 
the  blood  through  blood  vessels,  lungs,  and  heart  is  often 
spoken  of  as  two  circulations;  that  part  connected  with 
the  lungs  is  called  pulmonary,  or  lung  circulation]  and 
that  which  is  connected  with  the  rest  of  the  body  is 
named  systemic,  or  body  circulation,  but  as  it  is  one  con- 
tinuous flow,  it  is  better  to  consider  it  the  general  circu- 
lation. 

Pulmonary  Circulation. — The  simple  circulation  of 
the  blood  is  as  follows  ( Fig.  51 ) :  The  blue  blood  from  the 
veins  of  the  body  enters  the  right  auricle  (6),  passes 
through  the  valve  into  the  right  ventricle  (8),  then 
through  a  valve  into  the  pulmonary  artery  (13),  which 
divides  and  enters  the  lungs  (7).  Here  the  blood  ves- 
sels divide  very  much,  and  become  capillaries.  Then 
the  blood  is  collected  in  the  veins  of  the  lungs,  and  goes 
from  the  lungs,  and  enters  the  left  auricle  of  the  heart 
by  the  four  large  pulmonary  veins  (14),  two  for  each 
lung.  The  blood  enters  the  lungs  from  the  right  ven- 
tricle blue,  and  comes  from  them  red  in  color,  full  of 
oxygen.  This  is  called  the  pulmonary  circulation. 

Systemic  Circulation. — The  four  pulmonary  veins 
enter  the  left  auricle  carrying  red  blood,  and  the  blood 


CIRCULATION. 


93 


passes  through  the  valve  into  the  ventricle.  Then  it 
presses  past  another  valve,  and  reaches  the  aorta.  This 
large  artery  sends  one  fifth  of  the  blood  to  the  head  by 
two  branches,  and  the  rest,  by  other  branches,  goes  to 
the  organs  of  the  trunk  and  to  the  extremities. 

After  passing  into  myriads  of  small  arteries  of  the 
upper  and  lower  parts  of  the  body,  it  reaches  the  capil- 
laries, loses  its  oxygen,  gets  impure  and  bluish  in  color, 
and  flows  into  little  veins. 

The  small  veins  empty  into  larger 
ones,  and  finally  into  two  large 
trunks,  one  of  which  enters  the  right 


FIG.  52.  Portal  Circulation.— 1.  Gall 
Cyst ;  2.  Gastric  Artery ;  3.  Splenic  Ar- 
tery; 4.  Hepatic  Artery;  5.  Intestinal 
Artery ;  6.  Gastric  Vein  from  Stomach ; 
7.  Gastric  Vein  from  Spleen  and  Pan- 
creas ;  8.  Inferior  Mesenteric  from  Intes- 
tines ;  9.  Superior  Mesenteric  from  Intes- 
tines; 10.  Descending  Aorta;  L.  Liver 

(under  side);    VP.  Portal  Vein;    VC.  Vena  Cava  Ascendens;  11.  He- 
patic Veins. 


94 


PHYSIOLOGY. 
R  1516 


-  18   L 


35 


FIG.  53.  Diagram  of 
Blood  and  Lacteal  Cir- 
culation.— 1.  Vein  from 
Right  Arm;  2.  De- 
scending Vena  Cava;  3. 
Lung ;  4.  R.  Auricle ;  5. 
R.  Ventricle;  6.  He- 
patic Artery;  7.  Liver; 
8.  Portal  Vein ;  9.  Gas- 
tric Vein  j  10.  Superior 
Mesenteric  Artery ;  11.  Kidney ; 
12.  Aorta:  13.  Ascending  Vena  Cava;  14. 
Mesenteric  Vein;  15-16.  Right  Carotid 
Vein  and  Artery ;  17-18.  Left  Carotid  Vein 
and  Artery;  19.  Artery  of  Left  Arm;  20.  Vein  of  Left  Arm;  21.  Arch 
of  Aorta ;  22.  Pulmonary  Artery ;  23.  Four  Pulmonary  Veins ;  24. 
Left  Auricle ;  25.  Left  Ventricle ;  26.  Thoracic  Duct ;  27.  Splenic  and 
Gastric  Arteries ;  28.  Stomach ;  29.  Spleen ;  30.  Pancreas ;  30a.  Splenic 
Vein;  31.  Mesenteric  Vein;  32.  Small  Intestine;  33.  Receptaculum 
Chyli;  34.  Lacteal;  35.  Lacteals  and  Glands  of  Mesentery. 


CIRCULATION.  95 

auricle  from  above,  and  the  other  from  below  the  heart. 
Thus  it  comes  back  to  the  place  from  which  it  started. 

Things  that  Help  Circulation. — Although  the  heart 
is  the  chief  propeller  of  the  blood,  the  force  i's  not  enough 
to  account  for  motion  in  veins  and  capillaries  where  there 
is  no  pulsation.  Several  other  things  are  helpers.  These 
are:  The  pressure  of  muscles  against  the  blood  vessels; 
the  changes  taking  place  when  oxygen  is  given  up  in  the 
capillaries,  for  if  something  goes  into  the  tissue  from  the 
blood  something  else  must  hurry  to  take  the  place  it 
left;  the  changes  made  by  growth;  and  the  attraction  of 
the  corpuscles  for  the  walls  of  capillaries.  The  jnove- 
ments  of  the  chest  in  breathing  and  the  elasticity  of 
arteries  are  also  helpers. 


FIG.  54.  Section  of  a  Lobule  highly  magnified,  showing  Liver  Cells 
and  Blood  Capillaries. — 1.  Capillaries ;  2.  Cells. 

Portal  System. — The  circulation  also  includes  two 
special  divisions  that  are  often,  for  convenience,  consid- 
ered apart.  They  are  called  the  portal  and  the  absorbent, 
or  lymphatic,  systems. 


96 


PHYSIOLOGY. 


The  portal  (Fig.  52)  has  to  do  with  part  of  the  digested 
food.  All  the  food  material  that  seeps  through  the  walls 
of  blood  vessels  in  the  stomach  and  intestines,  and  all 
the  blood  from  these  organs  and  from  the  spleen  and 
pancreas  goes  to  the  liver. 

Notice  how  the  smaller  veins  on  each  side  of  the  stom- 
ach (28,  Fig.  53)  join  a  large  one.  Notice  how  many  veins 
run  into  the  short  portal  vein  (8,  Fig.  53),  and  think  of 
twenty-fi-ve  feet  of  intestines,  with  all  their  veins,  and 
you  get  some  idea  of  the  extent  of  this  system,  or  the 
amount  of  territory  drained  by  these  bluish  red  rivers. 


FIG.  55  (Copied).  Lobule  of  Liver  of  Rabbit.— 1.  Intralobular  Vein ; 
2.  Interlobular  Veins ;  3.  Bile  Canals  and  Capillaries. 

The  portal  system  starts  in  the  capillaries  of  the  ali- 
mentary canal,  and  these  capillaries  connect  with  small 
veins  that,  like  veins  elsewhere,  empty  into  larger  ones, 


CIRCULATION.  97 

till,  at  last,  the  blood  enters  the  liver  by  one  short,  stout 
vein,  about  four  inches  long  (Fig.  51,  V  P).  But  here 
a  strange  thing  takes  place.  The  large  vein  subdivides 
again  and  again,  much  as  arteries  do,  and  finally  ends 
in  capillaries,  as  it  began. 

The  capillaries  in  each  lobule  of  the  liver  run  among  the 
cells  and  connect  with  a  single  vein  in  the  center  of  the 
lobule,  called  the  intralobular  vein  (Figs.  54,  55).  The 
blood  from  the  intralobular  vein  flows  into  larger,  and 
then  larger  ones,  till  it  leaves  the  liver  by  the  hepatic 
veins  (11,  Fig.  52),  and  enters  the  large  trunk  that  runs 
up  to  the  right  auricle  of  the  heart  (Fig.  52,  V  C). 

The  peculiarity  of  the  portal  system  is  that  blood 
starts  in  capillaries  in  the  digestive  organs,  and,  before 
reaching  the  general  circulation,  runs  through  a  second 
set  of  capillaries  in  the  liver.  Now,  the  blood  always 
slows  up  in  capillaries,  so  this  circulation,  where  there  are 
two  interferences  with  its  speed,  goes  to  prove  the  state- 
ment that  something  more  than  heart  force  is  needed  for 
circulation. 

Portal  blood  is  a  mixture  of  food  element  and  the  blue 
blood  from  the  alimentary  canal.  The  digestive  organs 
and  the  liver  receive  red  blood  from  their  arteries,  which 
are  branches  of  the  aorta  (Figs.  52,  53). 

The  Lymphatic  System. — The  lymphatic  system 
(Fig.  56)  is  called  also  absorbent,  because  its  chief  work 
is  to  absorb  the  material  which  it  carries.  It  does  not 
get  it  by  circulation  from  other  vessels.  It  is  named  lym- 
phatic, because  the  fluid  oftenest  in  its  vessels  is  lymph. 
The  lymphatics  are  situated,  one  set  just  under  the  skin, 
and  another  deeper  down  in  the  muscles,  and  inside  the 
trunk  (Fig.  56).  They  r-un  along  through  nearly  all  the 
tissues,  close  beside  blood  vessels. 

Lymph  is  a  whitish  fluid,  something  like  the  plasma 


98 


PHYSIOLOGY. 


FIG.  56  (Copied).  Absorbent  System.— (Superficial  Lymphatics  show 
on  Head  and  left  Limbs ;  deep  ones  on  right.  Enlarged  white  masses 
are  glands),  c.  Termination  of  Thoracic  Duct;  a.  Thoracic  Duct;  i. 
Intestine  with  Lacteals  passing  to  Mesentery,  through  Glands  to  Re- 
ceptaculum  Chyli.  On  the  right  Lymphatic  Trunks  enter  large  Veins. 


CIRCULATION.  99 

of  blood.  The  lacteals  of  the  digestive  organs  (Fig.  53) 
belong  to  the  lymphatic  system,  and  carry  lymph  when 
they  are  not  busy  carrying  lacteal  fluid  to  the  thoracic 
duct.  The  difference  between  $ymph  and  lacteal  material 
is  that  the  latter  is  milky,  and  full  of  food  products;  the 
chyle  shows  through  the  walls  of  the  lacteals,  and  makes 
them  look  white. 

Valves  and  Glands. — Lymph  is  carried  in  very  fine 
vessels  that  have  valves  (3,  4,  Fig.  47),  and  the  valves 
are  so  numerous  that  the  vessels  look  beaded.  These 
vessels  are  connected  with  numerous  glands.  The  glands 
are  in  size  from  a  hemp  seed  to  an  almond.  The  beaded 
tubes  are  supposed  to  collect  the  liquid  blood  that  oozes 
through  blood  vessels  and  is  not  used  up  by  the  saturated 
tissues.  Perhaps  they  also  take  in  some  partially  wasted 
material,  and  carry  it  to  their  glands  to  be  changed,  and 
then  hold  all  the  material  till  it  is  needed. 

Nearly  all  the  lymphatics  of  the  system  empty  into 
the  thoracic  duct,,  and  send  their  fluid  into  the  general 
circulation  by  way  of  the  left  vein,  under  the  clavicle 
(20,  Fig.  53);  but  those  of  the  upper  right  side  enter  the 
right  vein  (4,  Fig.  56). 

Extra  Glands  That  Act  on  the  Blood.— There  are 

certain  glands  outside  the  digestive  and  the  lymphatic 
systems  whose  functions  are  of  great  importance  in  the 
preparation  of  blood.  These  glands  remove  harmful  ma- 
terials from,  or  reorganize  substances  in  the  blood.  The 
largest  glands  are  the  kidneys  and  spleen. 

The  Kidneys.  —  The  kidneys  are  two  small,  dark 
colored  glands,  situated  one  on  each  side  of  the  spinal 
column,  near  the  lowest  ribs.  Their  shape,  something 
like  a  Lima  bean,  is  shown  in  11,  Fig.  53,  and  the  kid- 
neys of  sheep  and  calves  in  the  markets  give  a  good 

7— P 


100  PHYSIOLOGY. 

idea  of  their  texture.  Nearly  all  the  waste  material  from 
lean  meat  and  such  foods  is  taken  from  the  blood  by  the 
kidneys,  and  also  much  of  the  waste  material  from  the 
tissues. 

The  skin  and  lungs  act  with  them,  and  if  one  of  these 
organs  becomes  diseased,  the  others  have  to  use  extra 
effort  to  get  rid  of  injurious  substances.  If  these  excre- 
tions do  not  leave  the  body,  they  are  taken  up  again  by 
the  blood,  and  circulate  around  among  the  tissues,  which 
are  already  clogged  with  their  own  constant  waste,  and 
the  consequence  is  temporary  discomfort  or  permanent 
disease.  It  causes  a  kind  of  poisoning. 

An  organ  can  only  for  a  short  time  help  its  fellow  that 
is  out  of  order,  for  the  supply  of  waste  material  is  large, 
and  each  part  of  it  has  its  regular  way  of  leaving  the 
body.  Each  organ  has  its  limit  of  capacity  for  work,  and 
if  it  is  overworked  it  becomes  unfit  for  its  usual  task. 

Spleen. — The  spleen  belongs  to  a  class  of  glands  that 
have  no  ducts,  and  until  lately  its  function  has  not  been 
well  understood.  It  is  supposed  to  change  certain  food 
elements,  and  thus  is  connected  with  digestion,  but  late 
investigations  show  that  it  also  has  much  to  do  with  the 
reorganizing  of  blood.  It  is  of  a  reddish  brown  color,  and 
is  situated  back  of  the  left  side  of  the  stomach.  It  is  said 
to  form  colorless  corpuscles,  and  to  break  up  partially  worn 
colored  ones,  and  to  form  new  colored  ones,  and  also  to  act 
as  a  reservoir  for  blood  when  anything  interferes  with  the 
portal  system.  It  changes  its  size  considerably  during 
the  day,  and  is  largest  several  hours  after  a  full  meal. 

There  is  a  peculiarity  connected  with  the  circulation  of 
blood  in  the  spleen.  Some  of  its  arteries  end  in  capil- 
laries, and  some  do  not.  In  the  latter  case  the  artery 
wall  stops  short;  there  is  no  blood  vessel  of  any  kind  to 
continue  it,  and  the  blood  escapes  among  the  tissues,  and 


CIRCULATION.  101 

forms  little  lakes.  Then  veins  connect  with  these  lakes, 
collect  the  blood,  and  carry  it  away  in  the  ordinary 
manner. 

Changes  in  Blood. — The  blood,  in  its  circuit  around 
the  body,  constantly  changes  in  composition  and  appear- 
ance. It  goes  through  a  process  of  loss  and  gain  as  it 
passes  through  all  the  organs. 

It  enters  the  lungs  blue,  and  filled  with  impure  air,  and 
when  it  leaves  them  it  is  red,  and  full  of  oxygen.  It 
enters  the  capillaries  of  nearly  all  organs  red,  and  loaded 
with  oxygen,  and  comes  out  blue,  and  burdened  with  im- 
pure air  and  waste  materials. 

It  carries  crude  food  and  waste  products  to  the  liver, 
and  carries  away  glycogen  sugar  and  changed  food.  It 
reaches  the  skin  laden  with  inorganic  salts  in  solution, 
injurious  gases,  and  waste  substance,  and  returns  without 
its  load.  It  also  carries  a  burden  of  waste  and  poisonous 
material  to  the  kidneys,  and  comes  back  purer.  It 
reaches  the  spleen,  bearing  quantities  of  broken  down, 
colored  corpuscles,  and  a  few  colorless  ones,  and  goes  away 
with  renewed  colored  and  many  more  colorless  cor- 
puscles. If  the  organs  do  not  do  their  duty,  the  blood  is 
not  good,  and  all  tissues  suffer. 

Dependence  of  Systems. — It  is  a  false  idea  to  con- 
sider the  systems  as  in  any  way  distinct.  No  matter 
where  we  start,  we  find  an  intimate  connection  and  de- 
pendence. It  is  difficult  to  describe  one  without  bringing 
in  parts  of  the  others.  This  is  especially  shown  in  diges- 
tion, circulation,  and  respiration.  For  example,  when 
food  is  taken,  it  is  digested  in  the  alimentary  canal, 
absorbed  by  absorbents,  carried  by  lacteals  to  the  thoracic 
duct  and  by  blood  vessels  to  the  liver,  and,  changed  by 
glands,  goes  to  the  lungs  for  oxygen,  which  the  near-by 
and  the  far-off  tissues  use  up  in  the  capillaries,  and  is 


102 


PHYSIOLOGY. 


circulated  till  it  finally  reaches  the  needy  parts,  where 
it  becomes  tissue.  The  nervous  system  controls  all 
others,  and  in  turn  is  affected  by  them.  Grief,  anger,  or 
any  great  nervous  excitement  will  as  surely  affect  diges- 
tion as  the  taking  into  the  stomach  of  a  quantity  of  clay. 


ORGANS   AND   FLUIDS   OF   CIRCULATION. 

ORGANS.  FLUIDS. 

Heart:  Two  auricles  (with  their  valves)  .     .  ^ 

Two  ventricles  (with  their  valves) 
Arteries,  veins,  capillaries      .          ... 

Pulmonary  artery 

Pulmonary  veins .  j.  Blood.  {  Plasma- 


Aorta 


Vena  Cava  ascending . 

Vena  Cava  descending •  .     . 

Portal  vein 

Lymphatics — Lacteals Lymph. 


L  Corpuscles. 


THOUGHT,  OB  OBSERVATION,  QUESTIONS. 

What  causes  variation  of  blood  ? 

Draw  both  kinds  of  corpuscles. 

Are  there  capillaries  in  the  skin  ? 

Are  there  valves  to  the  vessels  that  enter  the  heart  ? 

Draw  a  heart,  and  trace  circulation. 

How  does  blood  that  enters  the  liver  differ  from  that  which  enters 
the  heart  from  the  left  subclavian  vein  ? 

Do  all  veins  carry  blue  blood? 

How  does  poison  get  from  the  skin  to  the  heart  ? 

Does  the  blood  from  the  lower  extremities  pass  through  the  liver  ? 

Do  veins  from  spleen  and  pancreas  open  directly  into  portal  vein  ? 

How  does  the  waste  material  that  results  from  changes  of  stom- 
ach tissue  reach  the  kidneys  ? 

If  glycogen  sugar  is  needed  in  the  villi,  how  does  it  get  there? 

Is  there  any  fluid  but  pancreatic  juice  in  the  pancreas  ? 

Is  there  lymph  in  the  lungs  ? 

If  lacteal  glands  change  food  liquids,  what  do  lymphatic  glands  do? 


BREATHING    ORGANS. 


103 


CHAPTER  7. 

BREATHING    ORGANS. 

Blow  on  your  hand.  Stop  and  think  where  the  air 
comes  from.  Blow  as  long  as  you  can.  Hold  your 
breath  a  moment  and  see  if  you  can  blow  again.  You 
will  find  that  before  you  can  do  it  you  must  draw  in  air. 


FIG.  57.  Section  of  Lungs. — 1.  Larynx;  2.  Windpipe  (Trachea);  3. 
Bronchi  (Right  and  Left  Bronchus);  4.  Bronchial  Tubes;  5.  Aorta; 
6.  Descending  Vena  Cava;  7.  Gullet  ((Esophagus);  8.  Thoracic  Duct. 

Breathing". — Drawing  in  and  forcing  out  air  is  -called 
breathing,  or  respiration,  and  it  is  done  by  a  sepcial  set 
of  organs.  It  is  divided  into  inspiration  and  expiration. 
Air  not  only  goes  in  and  out  of  these  organs,  to  keep  all 
the  tissues  of  the  body  in  good  health,  but  it  causes 
speech,  laughter^  and  all  the  vocal  sounds  we  are  able  to 
produce.  Fig.  57  shows  the  chief  organs  of  respiration — 
the  lungs  and  air  tubes.  They  are  confined  to  the  head, 
neck,  and  upper  part  of  the  chest. 


104 


PHYSIOLOGY. 


Take  a  long,  deep  breath.  The  chest  rises,  the  ribs 
press  out,  the  waist  gets  larger,  and  if  the  inside  of  the 
trunk  could  be  seen  it  would  show  the  diaphragm  nearly 
straight  across.  The  contracting  or  relaxing  of  the  chest 
muscles  and  the  diaphragm  alters  the  capacity  of  the 
chest  and  causes  the  air  to  be  drawn  in.  This  action 
gives  the  lungs  the  greatest  amount  of  room.  Their 
elastic  tissue  expands,  and  the  air  rushes  in  to  fill  them. 
In  expiration  the  reverse  takes  place,  and  air  is  driven 
out  by  making  the  chest  cavity  smaller.  The  diaphragm 
is  considered  the  chief  muscle  of  respiration. 


I. 


II. 


FIG.  58  (Copied).  Air  Sacs  and  Tubes.— I.  Diagram  of  clusters  of 
Air  Sacs:  1.  Bronchial  Tube;  2.  Lobule;  3.  Lobule  cut  open,  show- 
ing internal  arrangement  of  Air  Sacs. 

II.  1.  Windpipe  ( Trachea) ;  2.  Bronchi  (Right  and  Left);  3.  Outline 
of  Left  Lung ;  4.  Bronchial  Tubes ;  5.  Cross  section  of  Trachea. 

Windpipe. — The -windpipe  (trachea)  is  a  tube  about 
four  inches  long,  situated  in  the  front  part  of  the  throat. 
It  is  stiff,  because  it  is  largely  composed  of  cartilage,  and 
it  can  be  easily  felt  as  the  hardest  part  of  the  throat. 
The  cartilage  is  in  many  pieces,  fastened  one  above  the 


BREATHING  ORGANS. 


105 


other,  and  shaped  something  like  a  horseshoe,  the  two 
ends  being  connected  by  softer  tissue  (5,  Fig.  58).  The 
separate  pieces  fastened  together  by  membranes  make 
the  tube  flexible.  The  gullet  rests  against  the  back  of 
the  windpipe  where  there  is  no  cartilage,  and  the  ab- 
sence of  this  stiff  material  allows  the  lump  of  food  to  pass 
down  easily. 

Cilia. — There  is  nothing  remarkable  about  the  wind- 
pipe, except  a  modification  of  its  mucous  membrane. 
Instead  of  the  outer  layer  of  this  membrane  being  made 
of  rounded,  or  flattened  cells,  as  in  the  mouth,  it  is  made 


FIG.  59.  Ciliated  Cells  (from  Calf).— 1.  Cilia ;  2.  Nucleus. 

of  column-like  cells.  The  top  of  each  little  cell  has 
fringes,  or  hair-like  projections.  They  are  called  cilia 
(Fig.  59).  Of  course,  they  are  microscopic.  The  fringes 
are  always  in  motion,  lashing  rapidly  backward  and  for- 
ward. They  cause  a  current  of  air  in  many  of  the  air 
tubes  which  drives  out  particles  of  dust.  As  they  are 
numerous,  always  busy,  and  always  drive  the  air  one  way — 
outward — it  can  be  understood  that  they  are  very  impor- 
tant little  bodies.  The  gills  of  clams  and  oysters  are  cov- 
ered with  similar  fringed  cells,  and  by  snipping  off  a  bit 
of  the  gill  and  putting  it  under  a  microscope,  the  sway- 
ing cilia  can  be  seen.  In  the  oyster  they  cause  a  current 


106 


PHYSIOLOGY. 


of  water  to  move  toward  the  animal's  mouth,  and  thus 
carry  in  food. 


PIGLOTTIS 


OCAL  CORDS 


TRACHEA 


II. 


FIG.  60.  Two  views  of  Larynx.— I.  Side.    1.  Adam's  Apple. 
II.  Back. 

Larynx. — Between  the  windpipe  and  the  back  of  the 
mouth  there  is  an  irregular  box  with  cartilaginous  walls 
(Fig.  57).  It  is  shaped  something  like  a  pyramid,  with 
its  base  uppermost,  and  its  cartilages  are  in  irregular 
pieces  bound  together  by  ligaments.  It  is  called  the 
larynx.  It  is  larger  across  than  the  windpipe.  In  men 
the  larynx  is  larger  than  in  women;  the  front  part  pro- 
jects, and  is  called  Adam's  apple. 

Glottis  and  Epiglottis. — The  upper  part  of  the 
larynx  is  called  the  glottis.  On  the  side  of  the  glottis 
nearest  the  tongue  there  is  a  spoon-like  projection  of  car- 
tilage, called  the  epiglottis,  that  serves  as  a  lid  to  close 
the  opening  of  the  larynx  (Fig.  60).  Notice  that  the 
windpipe  is  in  front  of  the  food  canal  (Fig.  35),  and 
food  has  to  pass  across  it  to  reach  the  stomach.  • 


BREATHING  ORGANS. 


107 


Air  is  going  up  and  down  the  windpipe  all  the  time  to 
the  lungs,  and  the  lid  must  be  lifted  to  let  it  pass.  A  little 
carelessness  when  we  eat  may  have  serious  or  fatal  con- 
sequences. Generally  when  we  swallow,  down  goes  the 
little  lid  and  the  food  slips  over  a  smooth  bridge  into  the 
gullet.  But  an  epiglottis  cannot  do  two  things  at  once. 
If  a  person  laughs  or  talks  when  trying  to  swallow,  the 
epiglottis  lifts  to  let  the  air  out  and  in,  and  if  it  is  not 
exceedingly  quick  to  shut  down  again,  the  chance  is  that 

a  bit  of  food  falls  into  the 
larynx.  This  causes 
choking.  The  food  is  said 
to  have  "gone  down  the 
wrong  way." 

Coughing  is    a  violent 
forcing   of  air   from   the 


I. 


II. 


FIG.  61  (Copied).— 1.  Vertical  section  through  Vocal  Organs:  1.  Epi- 
glottis; 2.  Vocal  Membrane,  or  "cords;  "  3.  Windpipe  (Trachea}:  4. 
Cartilages ;  5.  Glottis. 

II.  Diagram  of  cross  section  of  Larynx,  from  above,  showing  Vocal 
Membrane  across  Glottis:  1.  Cartilage;  2.  Vocal  Membrane,  attached 
on  all  sides  except  inner;  3.  Dotted  lines  indicate  attachment  and 
direction  of  the  ligament  "cords"  over  which  mucous  membrane  is 
stretched. 


108  PHYSIOLOGY. 

windpipe  and  larynx,  and  generally  serves  to  drive  out 
the  particle  of  food.  The  violence  of  the  effort  is  liable  to 
bring  tears  to  the  eyes  and  to  hurt  the  muscles  and 
mucous  membrane,  and  cause  soreness  of  the  throat. 
The  food  that  had  no  right  there  adds  to  the  injury. 

Vocal  Membranes. — In  the  larynx  are  situated  the 
most  important  organs  of  voice,  called  the  vocal  "cords" 
although  they  do  not  look  like  cords.  They  are  folds  of 
mucous  membrane,  and  extend  from  each  side  of  the 
larynx,  so  it  is  better  to  call  them  vocal  membranes  (Figs. 
60,  61 ) .  They  are  supported  on  ligaments.  The  loose  skin 
between  the  thumb  and  the  first  finger  gives  some  idea 
of  the  arrangement  of  one  of  these  membranes.  They  are 
exactly  opposite  each  other  and  very  thin  at  the  edges. 
They  vibrate  when  the  air  passes  through  in  speaking. 

When  the  muscles  that  control  them  are  tightened, 
and  the  membranes  become  tense,  the  free  edges  draw 
nearer  together  across  the  larynx,  so  that  there  is  only  a 
narrow  slit  between  them  (Fig.  61,  II.).  The  air  passing 
through  this  slit  gives  a  shrill,  high  tone  to  the  voice. 
When  the  membranes  relax,  the  voice  is  lower  and  less 
sharp.  By  holding  the  fingers  on  the  throat  while  mak- 
ing a  variety  of  sounds  one  can  feel  the  motion  and 
vibration  of  the  vocal  cords.  Any  thickening  of  the 
membrane  changes  the  voice. 

Delicate  muscles  control  the  larynx  and  vocal  mem- 
branes, and  make  many  changes  in  their  shapes,  which 
enable  us  to  produce  numerous,  different  sounds.  The 
tongue,  lips,  and  nasal  passages  help  in  the  production 
of  voice.  In  respiration  the  air  goes  up  and  down  past 
the  vocal  membranes,  but  makes  no  noise  unless  the 
muscles  adjust  the  vocal  organs  for  speaking.  Just 
above  the  vocal  membranes  there  are  other  folds,  one  on 
each  side  of  the  larynx,  called  the  "false  vocal  cords," 
but  their  use  is  not  well  understood. 


BREATHING  ORGANS.  109 

Bronchial  Tubes. — After  the  windpipe  has  extended 
about  four  inches  from  the  larynx,  it  branches.  One 
branch  enters  the  right,  and  the  other  the  left  lung  (Fig. 
58,  II.).  These  large  tubes  enter  the  lung  tissue  and 
subdivide,  something  like  arteries,  growing  smaller  and 
smaller  till  they  become  microscopic,  their  walls  becom- 
ing thinner  as  they  decrease  in  size.  The  small  branches 
of  the  two  divisions  are  called  bronchial  tubes.  They  end 
in  minute  sacs  (Fig.  58,  I.). 


FIG.  62.  Lung  section. — Capillary  Vessels  over  Air  Sac. 

Sacs. — The  air  sacs  are  numerous,  and  are  probably 
the  most  important  of  the  breathing  organs.  No  openings 
have  been  found  in  their  walls,  and  yet  gases  constantly 
pass  through  them. 

Air  and  liquids  have  the  ability  to  creep  through  moist 
animal  membranes  (page  79,  Osmose).  For  example,  if 
a  damp  bladder  is  filled  with  colored,  or  suffocating  gas, 
or  a  gas  with  any  marked  characteristics,  and  then  hung 
in  a  jar  filled  with  some  gas  without  many  peculiarities, 


110 


PHYSIOLOGY. 


the  two  gases  will  pass  through  the  walls  of  the  bladder, 
and  the  result  will  be  mixed  gases  in  both  places. 

Oxygen  gets  into  the  blood  corpuscles  through  the  walls 
of  the  air  sacs  and  changes  the  blood  from  blue  to  a  red 
color.  The  walls  of  the  sacs  are  very  thin  and  delicate, 
and  are  covered  with  a  network  of  capillaries  (Fig.  62). 
You  remember  that  the  capillaries  were  so  thin-walled 
that  plasma  passed  through  to  the  tissues.  In  this  place 
their  thin  walls  let  air  pass.  There  is  a  vast  difference 
between  the  air  that  comes  into  and  that  which  leaves 
the  lungs. 


EXPIRED    AIR. 

If  breathed  into  a  jar,  it  puts 
out  a  candle  placed  in  the  jar. 

Breathed  in  a  bottle  and  left, 
has  a  bad  odor. 

Has  much  water. 

Breathed  into  lime  water  makes 
it  milky  in  a  few  minutes. 


INSPIRED,  OR  ATMOSPHERIC,  AIR. 

A  candle  will  burn  in  it. 

Has  no  odor,  if  placed  in  a 

bottle  and  left. 
Has  some  water. 
Leaves  lime  water  clear. 

(Lime  water  left  exposed  to  air  for 
hours  gets  a  film,  but  this  is  due 
to  the  breath  of  men  and  ani- 
mals in  the  atmosphere.) 

By  a  little  thought,  you  will  perceive  what  causes 
these  differences.  It  is  the  wearing  out  of  tissue.  Cuti- 
cle can  be  seen  wearing  away  and  hair  falling  out,  and 
the  decay  of  teeth  is  unpleasantly  perceptible;  but  the 
wasting  of  other  tissues  can  only  be  learned  indirectly. 
For  example,  the  amount  of  food  taken  is  an  indication 
of  a  waste  to  be  repaired,  and  impure,  expired  air  is  an 
indication  that  tissues  have  exchanged  their  waste  for 
new  material  in  the  blood. 

Lungs. — The  lungs  are  one  of  the  principal  organs 
for  removing  waste  products.  The  lungs  are  of  two 
parts,  and  made  of  cellular  tissue  that  forms  air  cells 
and  supports  "air  tubes,  blood  vessels,  lymphatics,  and 
nerves.  They  are  pinkish  gray  in  color,  and  are  mottled. 


BREATHING  ORGANS.  Ill 

They  occupy  nearly  all  the  chest  cavity,  and  have  several 
divisions,  which  separate  them  into  lobes  that  are  thin  at 
the  edges. 

They  are  covered  with  a  thin,  serous  membrane,  called 
pleura  (9,  Fig.  37),  and  a  similar  membrane  lines  the 
chest.  These  membranes  are  so  smooth  and  moist  that 
they  glide  over  each  other  easily  during  all  the  motions  of 
breathing. 

Lung  tissue  is  elastic.  AVhen  the  lung  taken  from  a 
sheep  or  calf  is  pressed  down  with  the  finger,  it  springs 
back  in  place  when  the  pressure  is  removed.  The  lungs 
also  always  contain  a  certain  quantity  of  air,  for,  no  mat- 
ter how  long  the  breath  is  expired,  it  cannot  be  exhausted. 
For  this  reason,  a  bit  of  lung  thrown  into  the  water  will 
float. 


Larynx. 


RESPIRATORY     ORGANS. 

Glottis. 

Epiglottis. 

Adam's  apple.  Bronchial  tubes— Cilia. 


Vocal  cords.  Air  cells> 

Cilia-  Capillaries. 

Trachea.  Pleura. 

Connective  tissue  of  lungs. 
Diaphragm. 


THOUGHT,  OR  OBSERVATION,  QUESTIONS. 

Why  do  we  have  to  breathe  ? 

Why  do  we  breathe  faster  after  hurrying? 

What  becomes  of  all  the  oxygen  that  enters  the  air  cells? 

Is  it  muscular  contraction  or  osmose  that  gets  the  bad  air  out  of 
the  lungs? 

What  keeps  the  lungs  and  air  tubes  moist? 

What  would  happen  if  they  became  dry? 

Where  does  the  moisture  in  the  breath  come  from  ? 

What  would  happen  if  the  blood  brought  a  quantity  of  bad  gas  to 
a  bunch  of  air  cells,  and  found  them  shut  up  bv  the  pressure  of  a 
tight  dress? 


112 


PHYSIOLOGY. 


CHAPTER  8. 

THE    NERVOUS    SYSTEM. 

The  Brain. — The  brain,  as  the  chief  organ  of  the  nerv- 
ous system,  rules  the  whole  body.     By  its  means  we  are 

R  L 


I.  II. 

FIG.  63.— 1.  Top  view  of  Brain:  1.  Pia  Mater;  2.  Arachnoid;  3.  Dura 
Mater,  three  covers  of  Brain  partly  removed  from  left  Hemisphere ; 
Convolutions  of  Cerebrum,  all  covers  removed;  R.  Right  Hemi- 
sphere ;  L.  Left  Hemisphere. 

II.  View  of  right  side  of  Brain:  5.  Cerebrum,  or  large  brain;  6. 
Cerebellum,  or  small  brain;  7.  Medulla  Oblongata,  or  beginning  of 
Spinal  Cord. 

conscious  of  heat,  cold,  and  hunger;  of  ugly  and  beauti- 
ful things;  and  of  glorious  deeds  done  by  men  and  women 
before  we  were  born.  The  brain  controls  walking,  talk- 
ing, and  studying.  If  we  take  up  a  newspaper  we  find 
out  by  brain  action  what  is  going  on  in  the  world  thou- 
sands of  miles  away.  We  are  conscious  of  the  universe, 
because  we  think.  Every  child  knows  where  his  brain 
is,  and  that  it  is  a  thought  machine. 

Fig.  63  shows  how  human  brain  looks  with  the  brain 
box  removecj.  The  brains  seen  in  meat  markets  resemble 
ours  so  nearly  that  they  are  good  examples  of  color,  struct- 
ure, and  arrangement.  The  brain  is  soft — one  of  the 


THE  NERVOUS  SYSTEM. 


113 


softest  of  tissues,  and  in  color  is  part  white  and  part  gray. 
On  the  outside  it  has  many  folds,  called  convolutions. 
These  are  deeper  in  grown  people  than  in  children,  and 
deepest  in  brains  of  persons  of  great  intelligence.  The 
number  of  convolutions  is  an  indication  of  the  mental 
power  of  the  individual. 


11 


FIG.  64. — I.  Horizontal  section  through  Cerebrum :  8.  Corpus  Cal- 
losum,  connecting  "band  of  white  tissue,  binding  Hemispheres;  9. 
White  nerve  material ;  10.  Gray  nerve  material  outside. 
-II.  Vertical  section  through  'Cerebellum  and  between  Hemisphere^ 
of  Cerebrum:  5.  Cerebrum,  or  large  brain;  6.  Cerebellum,  or  small 
brain;  7.  Medulla  Oblongata,  gray  material  inside;  11.  Arrangement 
of  gray  and  white  material. 

The  brain  is  in  two  distinct  parts  (Figs.  63,  64). 


I.    CEREBRUM. 


Large,  upper,  in  front  (Fig.  62, 

II.,  5). 

Twisted  convolutions. 
Two  hemispheres. 


Gray  matter  in   short  projec 
tions  (Fig.  64,  I.). 


II.  CEREBELLUM. 


Small,  lower,  behind  (Fig.  63, 
II.,  6). 

Straight  across  folds. 

A  slight  depression,  making 
two  sides. 

Gray  matter  penetrating  deeply, 
forming  tree-like  branches 
(Fig.  64,  II.). 

The  hemispheres  are  so  distinct  that  only  their  con- 
necting band  of  white  tissue  would  be  cut  through  if 


114 


PHYSIOLOGY. 


FIG.  65.  Section  of  Spinal  Cord  from 
Neck,  Cervical  region.— 1.  Multipolar 
Cells  (Gray  material);  2.  Cut  ends  of 
Fibres  (White  material). 


they  were  separated 
from  each  other  (8, 
Fig.  64).  In  the  brain 
the  gray  matter  is  out- 
side the  white  and  is 
about  an  eighth  of  an 
2  inch  thick.  If  it  were 
spread  out  evenly  it 
would  cover  many 
feet  of  surface. 

Structure.— Gray 

matter  is  generally  in 
cells,  and  these  cells 
have  a  varying  num- 
ber •  of  projections 
(3,  Fig.  65).  White 
material  is  in  fibres 


I.  ii.  in. 

FIG.  6Q.— I.  Cross  section  of  Nerve :  1.  Ends  of  Nerve  Fibres ;  2.  Con- 
nective Tissue. 

II.  Bundle  of  Nerve  Fibres. 

III.  Njerve  Fibre:  1.  Sheath;  2.  Constriction,  Sheath  wanting. 


THE  NERVOUS  SYSTEM. 


115 


(Fig.  66,  II.).      Fibres  are  bound 
together  in  bundles,  and  cells  are 
held    in    position    by   connective 
QSM^M  tissue  (Figs.  65,  66,  I.). 

Spinal  Cord.— Fig.  63,  II.,  7, 
shows  a  white  portion  projecting 
below  the  brain.  It  is  the  begin- 
ning of  the  spinal  cord  (Fig.  67). 
It  passes  out  of  the  skull  through 
an  opening  in  its  under  side  (13, 
Fig.  35).  The  spinal  cord  is  part 
of  the  nervous  system,  and  extends 
from  the  head  to  the  lower  part  of 
the  first  lumbar  vertebra  (Fig.  67, 
c').  It  varies  in  size  (Fig.  68).  It 
differs  from  the  brain  in  having 
the  white  nerve  material  on  the 
outside  and  gray  inside. 


FIG.  68.  Cross  section 
of  Spinal  Cord  (natural 
size). — a  and  b.  Lumbar 
Region ;  c.  Medulla  Ob- 
longata;  1.  Gray  mate- 
rial ;  2.  White  material. 


FIG.  67  (Copied).  Vertical  section  through 
Skull  and   Spinal  Canal,   showing  Brain 

and  Spinal  Cord  in  place. — a.  Cerebrum;  6.  Cerebellum;  c.  Spinal 
Cord;  c'  Place  where  Spinal  Cord  stops;  e.  Cauda  Equina  (Horse's 
tail)  mass  of  nerves  from  Spinal  Cord;  s.  Sacral  Plexus;  n.  Sciatic 
Nerve;  x.  Iimominata  Bone. 


116 


PHYSIOLOGY, 


Nerves. — Branches  extend  from 
the  spinal  cord  and  are  called 
nerves  (Fig.  69,  c).  They  extend 
to  all  parts  of  the  body,  subdividing 
till  they  become  microscopic  fila- 
ments.. Nerve  branching  is  differ- 
ent from  the  branching  of  any  other 
organs  of  the  body.  In  blood  ves- 
sels a  smaller  tube  ends  in  a  larger 
one.  A  nerve  filament  merely  en- 
ters a  bundle  of  filaments,  keeping 
its  individual  fibre  distinct  from  all 
other  fibres  from  the  time  it  starts 
till  it  reaches  its  destination.  So 
a  nerve  is  nothing  but  a  bundle  of 
threads,  something  like  a  skein  of 
silk  (Fig.  66, 1.,  II.),  and  the  white 
JJ""-  matter  of  the  spinal  cord  is  only 

a  larger  bundle  of  threads. 

Function. — The  most  important 
thing  about  a  body  is  the  work  it 
can  do.  Nerve  material  has  to 
superintend  the  working  of  all 
other  systems,  and  as  there  are  two 
kinds  of  material  each  has  its  own 
particular  duty.  The  cells — gray 
matter — receive  impressions  and 
direct  all  action;  the  fibres — white 
matter — carry  messages. 

FIG.  69  (Copied}.  Under  side  of  Brain  and 
Spinal  Cord.— Cranial  Nerves:  1.  Olfactory 
Nerves;  2.  Optic  Nerves;  3.  Motor  Nerves 
of  Eyeball ;  4.  Pathetic  Nerves ;  5.  Fifth 
Pair  Nerves  (Trigeminal);  6.  Sixth  Pair;  7.  Seventh  Pair  (part  is  Au- 
ditory Nerve);  8.  Eighth  Pair  (of  three  parts);  9.  Ninth  Pair,  Hypo- 
glossal;  a.  Cerebrum;  6.  Cerebellum ;  m.  Medulla Oblongata ;  c.  Spinal 
Cord  with  nerves  branching  from  each  side;  e.  Cauda  Equina;  ax.  Ax- 
illary Plexus ;  /.  Lumbar  Plexus ;  s.  Sacral  Plexus ;  t.  Sheath  of  Cord. 


THE  NER  VO  US  SYSTEM.  117 

The  system  is  something  like  that  of  the  telegraph.  In 
the  telegraphic  system  the  wires  run  from  all  directions  to 
various  offices.  In  each  an  operator  learns  what  messages 
they  bring  and  sends  back  orders  or  answers.  An 
operator  can  tap  the  wires  anywhere  and  learn  what  is 
going  over  them. 

In  the  nervous  system  the  fibres  are  like  the  wires,  and 
the  cells  like  an  operator.  Wherever  cells  occur  they  can 
take  the  sensations  and  give  the  orders.  But  they  do 
not  send  back  orders  by  the  same  wire  that  brought  the 
message,  as  the  telegraph  operator  does.  When  a  cell 
operator  in  the  nervous  system  receives  a  notice  of  sen- 
sation by  one  nerve  fibre,  it  sends  back  an  order  for 
motion  by  another,  and  hence  the  first  is  called  a  sensory 
nerve,  and  the  other  a  motor  nerve. 

One  of  each  kind  is  bound  in  a  single  sheath,  and  there 
is  no  visible  difference  between  them,  but  they  never  get 
mixed  up  and  do  each  other's  work.  The  filaments  extend 
to  the  papillse  of  the  whole  surface  of  the  body  (Fig.  24). 
Now,  if  a  person  puts  his  hand  on  something  hot,  instantly 
the  fibres  of  the  sensory  nerve  carry  the  impression  to 
some  place  where  there  are  gray  cells;  they  receive  the 
impressiQn,  and  immediately  send  orders  for  muscles  to 
pull  the  hand  out  of  danger.  The  rapidity  of  nerve  action 
is  seen  in  the  quickness  with  which  one  jerks  his  hand 
from  hot,  or  harmful,  things,  but  every  time  the  nerve 
has  to  carry  messages  two  ways  before  the  hand  is 
snatched  away. 

The  order  is  so  promptly  obeyed  by  the  muscles  that 
we  forget  that  they  have  had  to  learn.  The  fact  that  a 
little  baby  would  hold  its  hand  in  the  fire  and  cry  with 
pain  without  knowing  enough  to~  pull  it  out,  and  that  a 
grown  person  would  instantly  pull  his  hand  away,  shows 
that  muscles  and  nerves  of  older  people  have  been  edu- 
cated. 


118  PHYSIOLOGY. 

Sensation  Seems  at  the  Surface. — We  feel  or  are 
conscious  of  pain  by  means  of  the  gray  cells  in  the  brain, 
but  the  filament  in  the  papillae  is  the  place  we  think  of  as 
hurt.  For  example,  if  a  nerve  that  reaches  the  finger  is 
cut  in  two,  and  the  cut  end  irritated,  we  think  the  hurt  is 
at  the  end  of  the  finger.  Often,  a  person  who  has  lost  a 
hand  or  foot,  when  the  maimed  limb  is  chilled,  thinks 
that  his  foot  or  hand  is  cold. 

Educated  Nerve. — All  the  good  and  the  bad  charac- 
teristics of  objects  ure  learned  through  the  sensory  nerves, 
and  all  motions  are  directed  by  the  motor  nerves.  But 
how  can  a  boy  learn  his  lessons  by  means  of  a  soft,  pulpy 
mass  no  thicker  than  jelly  and  not  quite  so  lively  look- 
ing? And  how  can  he  recite  them  by  means  of  gray 
cells  in  his  head  sending  messages  of  motion  by  white 
fibres  to  the  delicate  muscles  of  his  vocal  cords? 

These  things  are  part  of  the  power  of  educated  nerve 
material.  A  savage  cannot  study  a  lesson,  but  a  civilized 
child  can.  He  has  learned  how.  His  gray  cells  have 
learned  that  written  words  stand  for  certain  things,  and 
they  recognize  them  by  sight,  and  his  white  fibres  have 
learned,  by  years  of  experience,  to  direct  vocal  muscles 
how  to  recite  words. 

Words  are  learned  by  much  patient  care  and  thought 
as  soon  as  the  brain  is  developed  enough  for  a  child  to 
imitate  action  in  others.  A  baby  has  to  be  taught  words, 
and  everything  else,  and  a  child  does  not  learn  any- 
thing from  books  till  he  knows  a  great  many  names  of 
objects,  and  has  many  ideas  about  the  things  surround- 
ing him. 

Ideas. — But  the  brain  has  ideas  of  things  that  no 
man  has  ever  seen,  some  of  which  we  call  honor,  love  of 
country,  religion,  and  immortality.  They  have  no  mate- 
rial in  them,  as  have  glass  and  gold  and  fine  raiment. 


THE  NER  VO US  SYSTEM.  119 

You  cannot  touch  or  see  them,  yet  the  bravest  and  finest 
thing  gray  cells  can  do  is  to  consider  them  well.  On  the 
whole,  they  are  the  most  important  things  of  life,  and  the 
most  real. 

Function  of  Brain. — There  would  be  no  use  in  hav- 
ing so  many  parts  to  the  nervous  system  if  there  were  not 
a  division  of  labor.  The  large  brain  controlling  volun- 
tary muscle  and  taking  note  of  color,  shape,  and  charac- 
teristics of  external  things,  is  the  seat  of  consciousness 
and  will  power;  it  originates  ideas  of  non-material  things 
and  forms  judgments  of  right  and  wrong,  and  controls 
the  intellectual  and  moral  nature.  If  it  is  injured,  the 
mind  is  impaired  or  destroyed.  The  cerebellum  regu- 
lates muscular  action.  If  it  is  injured  or  removed,  the 
muscles  act,  but  in  an  irregular  and  spasmodic  way. 

Reflex  Action. — The  spinal  cord  is  a  large  bundle  of 
fibres  for  transmitting  impressions  and  orders,  but  it  has 
gray  cells,  and  these  little  operators  can  tap  the  wires. 
Thus,  when  a  slight  sensation  is  sent  along  a  nerve  it 
does  not  always  reach  the  brain.  It  is  taken  ofT  by  the 
nearest  cell,  and  the  gray  matter  here  sends  back  an 
order  for  muscular  action  without  our  consciousness. 
This  unconscious  action  is  called  rejl&z^  action.  The 
motion  of  a  person  asleep,  who  stirs  when  touched,  is  of 
this  kind.  A  great  many  daily  actions,  such  as  walking 
when  we  have  decided  where  to  go,  and  some  motions 
we  have  learned  with  difficulty,  are  of  this  kind.  Pos- 
sibly much  of  the  talk  we  hear  is  merely  reflex  action. 

The  cells  which  thus  arrest  sensation  save  the  brain  a 
great  deal  of  labor.  The  spinal  cord  is  an  organ  of 
reflex  action.  Some  nerve  centers  in  the  brain  also  con- 
trol reflex  action. 

Crossing  of  Nerves. — The  spinal  cord  is  made  of 
four  columns  of  fibres,  two  in  front  and  two  back,  closely 


120 


PHYSIOLOGY. 


pressed  together.     The  nerves  that  enter  it  have  a  strange 
way  of  crossing  to  the  opposite  side  and  reaching  the 


Li 


S     C 


a     p 


FIG.  70.  Diagram  of  Medulla  Oblongata,  Spinal  Cord,  and  three  pairs 
of  Spinal  Nerves.  (Also  shows  how  an  injury  at  x,  destroying  half  of 
Spinal  Cord,  affects  sides  of  body.) — S.  C.  Spinal  Cord;  a.  Anterior 
columns  of  Spinal  Cord ;  p.  Posterior  columns  of  Spinal  Cord ;  8.  Sen- 
sory Nerve,  and  M.  Motor  Nerve,  join  in  one  sheath  after  leaving  Spinal 
Column;  M.  0.  Medulla  Oblongata;  1,  2,  3.  Three  pairs  of  Spinal 
Nerves;  R.  Rigjit  side;  //.Left  side;  — -^Direction  of  Nerve  Im- 
pulse; x.  Location  of  an  injury.  Dotted  lines  show  Sensory  Fibres 
passing  back  of  Anterior  to  reach  Posterior  Columns. 

other  side  of  the  brain,  and  this  gives  rise  to  some  queer 
effects.     The  reason  a  blow  on  one  side  of  the  head  affects 


THE  NER  VO  US  S  YSTEM.  121 

the  other  side  of  the  body,  and  the  reason  an  injury  on 
one  side  of  the  spinal  cord  destroys  sensation  of  one  side 
and  motion  of  the  other  side  of  the  body,  are  perfectly 
easy  to  understand,  if  you  will  examine  Fig.  70,  and 
remember  seven  things: 

1 .  Motor  and  sensory  nerves  are  distinct. 

2.  They  reach  the  spinal  cord  in  a  single  sheath. 

3.  The  spinal  cord  is  made  of  front  and  back  columns. 

4.  The  motor  nerves,  upon  reaching  the  spinal  cord,  go 
up  the  front  column,  and  cross  at  the  medulla  oblongata. 

5.  The  sensory  nerves  cross  to  opposite  side  of  back 
column,  immediately  upon  reaching  the  spinal  cord. 

6.  Right  motor  and  sensory  nerves  reach  the  left  side 
of  the  brain. 

7.  Left  motor  and  sensory  nerves  reach  the  right  side 
of  the  brain. 

Thus  the  right  side  of  your  brain  receives  impressions 
from  the  left  side  of  the  body,  and  directs  the  action  of 
that  side.  By  tracing  these  crossings  of  fibres,  it  is  easy 
to  know  the  reason  of  some  effects  that  follow  injury  of 
the  brain,  like  paralysis,  partial  paralysis,  and  injury  of 
the  spinal  cord. 

Cranial  and  Spinal  Nerves. — There  are  two  divis- 
ions of  nerves  (Fig.  69).  One  set  branches  from  the 
brain,  and  only  a  few  of  them  pass  beyond  the  skull. 
They  are  the  cranial  nerves.  There  are  twelve  pairs. 

The  other  set  springs  from  the  spinal  cord,  and  extends 
to  all  parts  of  the  surface  of  the  body.  There  are  thirty- 
one  pairs,  and  they  are  called  spinal  nerves.  They  pass 
through  the  bones  of  the  spinal  column  by  means  of 
small  openings  at  the  sides,  which  can  be  seen  in  Fig.  11. 

Coats. — The  nerves  are  covered  by  a  sheath,  and  the 
brain  and  spinal  cord  are  protected  by  three  coats*  Fig. 
03  shows  portions  of  each  of  these  coats  on  one  half  the 


122  PHYSIOLOGY. 

brain.  The  inside  coat  is  next  to  the  nerve  matter,  and 
is  very  thin,  and  full  of  vessels;  the  middle  coat  is  made 
of  two  very  thin  serous  membranes,  between  which  there 
is  a  liquid.  This  liquid  and  the  membranes  act  as  a 
water  cushion  to  protect  the  brain  from  a  jar  or  a  blow. 
The  third,  or  external  membrane,  is  dense  and  fibrous, 
and  lines  the  part  next  to  the  bone. 

Sympathetic  Division  of  Nervous  System.— The 
brain  and  spinal  cord,  cranial  and  spinal  nerves  have 
very  little  to  do  with  the  involuntary  muscles,  with  diges- 
tion, circulation,  and  respiration.  There  is  a  special 
division  of  the  nervous  system,  named  sympathetic,  that 
generally  controls  them.  It  is  called  sympathetic,  be- 
cause one  part  of  the  body,  by  means  of  these  nerves,  is 
easily  affected  by,  or  sympathizes  with,  any  other  part 
that  is  in  pain,  or  out  of  order.  It  is  composed  of  many 
thread-like  nerves  and  bunches,  made  up  of  nerve  cells 
and  fibres,  and  looks  something  like  a  loose  net  with 
floats  (3,  Fig.  71). 

Ganglia. — The  bunches  are  called  .ganglia  (singular, 
ganglion),  and  are  also  found  in  the  brain.  The  ganglia 
of  this  system  are  arranged  in  two  principal  lines,  inside 
the  trunk,  one  on  each  side  of  the  spinal  column,  and 
branches  of  the  system  extend  to  all  the  vital  organs,  and 
also  extend  to  the  cranial  nerves  and  spinal  cord* 

The  gray  matter  in  the  cells  acts  as  little  brains,  and 
controls  the  functions  of  the  vital  organs.  Food  cannot 
digest  without  the  motions  of  stomach  and  intestines,  and 
the  dissolving  action  of  digestive  juices;  these  juices  can- 
not form  unless  blood  brings  the  right  material" to  the 
glands  that  secrete  them;  blood  cannot  flow  unless  heart 
and  blood  vessels  contract  and  relaxx  and  none  of  these 
organs  can  act  without  impulse  from  the  sympathetic 
nervous  system, 


THE  NERVOUS  SYSTEM. 


123 


FIG.  71  (Copied).  Parts  of  Cerebro-spinal  and  Sympathetic  Nervous 
Systems  (right  side). — 1.  Superficial  Facial  Nerves;  2.  Cervical  Nerves ; 
3.  Sympathetic  Nerves  and  Ganglia  branching  to  Heart,  Stomach, 
Kidney,  Intestines,  Lungs;  4.  Brachial  Nerves;  5.  Brachial  Artery; 
6.  Intercostal  Nerves ;  s.  Stomach ;  h.  Heart ;  k.  Kidney ;  i.  Intestines. 


124  PHYSIOLOGY. 

Inter-dependence    of    the    Two    Systems.— In 

health,  this  system  takes  all  the  responsibility  of  con- 
trolling the  functions  of  the  internal  organs,  without  call- 
ing our  attention  to  their  operations;  but  if  anything 
gets  out  of  order,  messages  are  sent  to  the  brain,  and  we 
are  conscious  of  pain. 

If  a  person  goes  too  long  without  food  there  is  a  gen- 
eral uneasiness  of  the  vital  organs.  Tissues  on  all  sides 
are  calling  for  material  and  there  is  no  food  in  the  ali- 
mentary canal.  The  nerves  from  the  stomach  and  intes- 
tines send  messages  of  need  to  the  gray  cells  of  the 
sympathetic  system,  only  to  have  the  knowledge  sent 
back  that  orders  for  digestion  are  useless  unless  there  is 
food  to  digest. 

Then  a  great  effort  is  made  and  a  message  runs  along 
the  nerve  that  goes  to  the  spinal  cord  away  up  to  the  brain, 
and  the  man  knows  he  is  hungry.  He  gets  food  if  pos- 
sible. When  the  food  comes,  the  sympathetic  nerves 
start  the  digestive  juices  out  of  their  glands,  set  the  in- 
voluntary muscles  to  working,  and  cause  the  blood  vessels 
and  lacteals  to  begin  absorbing,  and  new  material  soon 
goes  to  all  the  hungry  tissues. 

If  a  person  eats  too  much,  or  something  difficult  to 
digest,  the  sympathetic  system  acts  as  in  ordinary  eating, 
but  is  unable  to  dispose  of  the  difficulty,  and  is  compelled 
to  call  for  help  on  the  brain  and  spinal  cord  divisions,  as 
it  always  does  in  emergencies.  In  all  such  cases  our 
intelligence  is  acted  upon  by  means  of  nerves  connecting 
the  two  systems,  and  the  mind  must  think  of  relief 
measures.  In  this  case  it  thinks  of  medicine  to  relieve 
pain  in  the  stomach,  and  thus  furnishes  relief. 

The  intimate  connection  of  these  two  parts  of  the 
nervous  system  is  shown  by  the  influence  that  many 
purely  mental  actions  have  on  involuntary  functions. 
Grief,  joy,  fright,  and  almost  any  excitement  will  often 


THE  NERVOUS  SYSTEM.  125 

take  away  all  desire  for  food.  The  thought  of  going  on 
a  pleasant  journey  often  spoils  a  child's  appetite. 
Thought  of  juicy  fruit  makes  the  mouth  water.  Anger 
sometimes  causes  a  change  in  the  secretion,  and  the  bite 
of  an  angry  man  is  said  to  be  as  poisonous  as  that  of  a 
mad  dog  or  wolf. 

ORGANS   OF   NERVOUS    SYSTEM. 

r  Cerebrum— Two  hemispheres. 
Cerebellum. 

Cerebro-Spinal  Division.  I  Medulla  Oblongata. 
j  Spinal  Cord. 

f  Motor. 
lNerV6S-  I  Sensory. 

Sympathetic  Division.    .  (  Nerve  Fibres. 
*  1  Ganglia. 


THOUGHT  QUESTIONS. 

Name  three  different  places  where  gray  matter  is  found.  Is  it 
in  the  hand? 

Name  three  peculiarities  of  spinal  nerves. 

Can  nerve  fibres  be  seen  the  same  as  meat  fibres  ? 

Did  you  ever  see  a  nerve? 

What  is  the  English  name  for  the  lower  part  of  the  spinal  cord? 
Do  you  see  any  resemblance? 

What  is  the  difference  between  the  upper  and  lower  part  of  the 
spinal  cord? 

How  do  you  know  glass  is  smooth? 

How  do  you  know  its  edges  will  cut  ? 

If  a  large  nerve  could  be  pinched,  what  would  be  the  consequence  ? 

What  is  the  difference  in  manner  of  learning  of  a  pain  in  the  foot 
and  one  in  the  stomach  ? 

How  is  a  person  frightened? 

Why  are  some  persons  more  timid  than  others? 

Trace  the  connection  between  touching  an  unseen  prickly  object, 
knowing  it  is  prickly,  and  pulling  the  hand  away. 

If  a  nerve  is  diseased  or  destroyed  in  the  arm,  how  does  it  affect 
the  arm  ? 


126  PH  YSIOL  OGY. 

Why  does  not  a  child  have  to  stop  and  think  of  snatching  his 
hand  from  something  that  is  hot,  as  he  has  to  think  about  an 
example  in  arithmetic? 

Why  are  some  examples  hard  to  understand  ? 

What  is  the  difference  between  knowledge  of  a  color,  and  know- 
ing it  is  wrong  to  tell  a  lie  ? 

If  part  of  the  gray  matter  of  the  brain  is  destroyed,  or  changed 
to  something  else,  what  will  be  the  effect  when  nerves  bring  an 
important  message  there  ? 

If  a  right  foot  is  hurt,  which  side  of  the  brain  knows  it ;  how  did 
the  impression  get  there? 

If  the  right  side  of  the  spinal  cord  is  injured  at  the  neck,  how 
will  the  extremities  be  affected? 

If  the  right  side  of  the  brain  is  injured,  can  you  feel  and  move 
the  right  side  of  the  body? 

If  the  front  columns  of  the  spinal  cord  are  injured  in  the  middle 
of  the  back,  how  will  the  extremities  be  affected  ? 

Can  a  man  live  or  walk  with  his  back  broken  ? 

Does  distortion  of  spinal  column  injure  brain  action? 


SPECIAL  SENSES.  127 

CHAPTER  9. 

SPECIAL    SENSES. 

The  knowledge  of  external  objects  is  obtained  by  a 
number  of  organs  of  the  body — the  skin,  nose,  mouth, 
ears,  and  eyes.  A  man  who  cannot  taste  or  smell  is 
liable  to  eat  injurious  things,  or  be  poisoned  by  bad  gases, 
and  a  blind  man  is  cut  off  from  the  greatest  enjoyment 
of  life,  and  must  be  led  by  other  people. 

As  each  organ  does  special  work,  they  are  called  organs 
of  the  special  senses.  They  are  the  highest  and  most 
delicate  organs  of  the  body.  Their  nerves  are  well  pro- 
tected. Although  all  nerves  are  of  the  same  soft  mate- 
rial, the  nerves  of  the  higher  senses,  as  sight  and  hearing, 
have  a  higher  power. 

Nerves  terminating  in  the  skin  carry  to  the  brain 
impressions  of  heat,  cold,  roughness,  smoothness,  hard- 
ness, and  softness;  nerves  from  the  mouth  take  sensa- 
tions of  taste,  and  from  the  nose  those  of  smell;  the  ear 
catches  and  transmits  sounds;  and  the  eye  gives  impres- 
sions of  color,  and  of  shapes  we  cannot  touch. 

Touch.. — The  sense  of  touch  seems  the  lowest,  and  its 
nerves  are  the  most  widely  distributed,  being  found  in 
the  skin  of  the  entire  body  surface.  If  anything  touches 
the  skin,  immediately  a  message  runs  rapidly  along  the 
white  nerve  of  sensation,  and  we  know  by  the  impression 
it  makes  on  the  gray  cells  that  the  object  is  pleasant  or 
unpleasant  to  the  touch.  If  it  is  unpleasant,  the  order 
is  instantly  carried  by  the  nerve  of  motion  for  muscles  to 
contract,  and  the  body  is  drawn  away  from  the  object. 

The  nerves  of  touch  are  in  the  papillae  of  the  true  skin. 
The  curved  ridges  at  the  ends  of  the  fingers  are  rows  of 
papillae.  These  terminations  are  called  touch  corpuscles. 


128  PHYSIOLOGY. 

and,  like  many  important  workers,  they  are  microscopic. 
In  fact,  they  are  so  exceedingly  small  that  it  is  not  settled 
beyond  a  doubt  just  how  they  are  arranged,  but  it  is 
thought  they  are  in  minute  coils  in  the  papillae. 

They  are  very  close  together  in  some  places,  and  in 
others  are  a  quarter  of  an  inch  apart.  Where  they  are 
farthest  apart,  feeling  is  not  so  acute.  They  are  crowded 
together  on  the  lips  and  the  tips  of  the  fingers,  while  on 
the  arms  and  the  back  of  the  thighs  they  are  farther 
apart.  Touch  a  piece  of  dress  goods  with  the  fingers, 
and  then  with  the  lips,  to  find  where  the  sensation  is 
most  acute. 

Take  two  pins  and  hold  their  points  close  together, 
and  touch  the  body.  Wherever  two  impressions  can  be 
felt,  it  is  an  indication  that  separate  nerve  terminations 
have  been  touched.  In  most  places  on  the  surface  of  the 
body  both  points  give  but  one  impression. 

Touch  has  been  called  the  universal,  or  common,  sense, 
and  though  differing  in  degree  with  different  people,  no 
one  has  ever  been  known  to  be  destitute  of  this  sense. 
The  other  senses,  one  or  all  of  them,  are  sometimes  either 
entirely  absent  or  but  slightly  developed. 

Education  of  Touch. — Touch  can  be  highly  edu- 
cated. Watchmakers,  workers  on  optical  instruments, 
musicians,  and  physicians,  are  people  who  have  educated 
touch.  The  muscles  of  their  hands  are  also  well  edu- 
cated, and  the  skin  on  their  fingers  is  not  allowed  to  get 
hard  and  callous. 

Blind  people,  having  to  depend  largely  on  this  sense, 
have  it  very  delicately  trained.  They  can  feel  peculiar- 
ities in  objects  never  thought  of  by  people  who  see.  It 
is  a  mistake  to  believe  they  can  detect  color.  There 
is  nothing  in  color  that  appeals  to  any  sense  but  sight. 
Bead  workers,  or  any  blind  people  who  work  in  colored 


.SPECIAL  SENSES. 


129 


FIG.  72  (Copied).  Tongue. — 1.  Circumvallate  Papillae;  2.  Circum- 
vallate  Papilla,  large;  3.  Toad-stool  (Fungiform)  Papillae;  4.  Thread- 
form  (Filiform)  Papillae. 

patterns,  know  the  different  colors  by  the  size,  shape, 
roughness  of  the  material,  or  by  its  position  in  the  box. 
Certain  dye  stuffs  make  fabrics  harsher,  and  it  is  a  mat- 
ter of  memory  and  association  of  the  name  of  a  color 
with  smoothness  or  roughness,  when  a  blind  man  says  a 
piece  of  goods  is  green,  black,  or  any  other  color. 

Taste. — The  little  thread-like  projections  easily  seen 
on  your  tongue  are  small  tubes,  in  which  the  taste  nerves 
begin.  Press  them  apart.  Some  are  more  blunt  than 
others  (Figs.  72,  73).  There  are  none  on  the  under  side 
of  the  tongue,  but  plenty  on  the  sides  and  top.  There 
are  three  kinds.  Two  can  be  seen,  but  the  third  kind  is 
almost  too  far  back  to  be  visible  (Fig.  72).  A  few  of  the 
taste  papillae  are  found  in  the  palate.  They  give  impres- 
sions of  salt,  sweet,  and  sour  articles,  but  cannot  act  un- 
less the  substances  are  dissolved. 


130 


PHYSIOLOGY. 


FIG.  73.  Section  of  Tongue.— 1.  Fungus-shaped  Papilla  (Fungiform) ; 
2.  Thread-shaped  Papilla  (Filiform)-,  3.  Blood  Vessel;  4.  Muscle;  5. 
Filiform  Papilla,  uncut. 

Mixed  Impressions. — The  senses  of  smell  and  taste 
so  act  together  that  people  are  apt  to  mix  the  impres- 
sions and  say  a  substance  has  a  had  or  good  taste,  when 
it  is  nearly  tasteless,  but  has  a  strong  odor.  This  is  the 
case  with  many  articles;  for  example,  there  is  scarcely 
any  taste  to  onions  or  vanilla.  The  mere  taste  of  an 
article  can  be  told  with  the  nostrils  closed.  This  pre- 
vents a  current  of  air  from  passing  over  the  article  in 
the  mouth  and  carrying  its  odor  to  the  nerves  of  smell. 
Notice  the  mouth  and  nose  cavities  (Fig.  35). 

Many  disagreeable  medicines  can  be  swallowed  with- 
out unpleasant  sensations  by  merely  holding  the  nostrils, 
because  they  are  really  almost  wholly  destitute  of  taste; 
but  half  the  enjoyment  of  good  food  would  be  taken 
away  by  the  same  act.  A  good  illustration  of  the  rapidity 
of  nerve  action  is  shown  by  the  quickness  with  which  a 
bad  tasted  object  is  put  from  the  mouth. 

Nerves  of  Sensation. — There  are  also  nerves  6"f 
general  impression,  as  of  cold  and  heat  in  the  mouth, 
and  they  are  more  sensitive,  because  they  are  less  pro- 


SPECIAL  SENSES. 


131 


tected  by  membrane 
than  those  on  the  out- 
side surface.  They 
carry  impressions  of 
pungent  and  spicy 
substances,  such  as 
mustard  and  pepper. 
Smell.— Fig.  74 
shows  how  the  fila- 
ments of  the  nerve 

FIG.  74  (Copied).  Nasal  Cavity .— 1.  Olfac-  of  Smell  Spread  over 

tory  Nerve  and  bulb ;    2.  Olfactory  Nerve  , ,  ,     f  , , 

fibres  on  Turbinated  portion  of  Ethmoid  the.  upper  part  Ol  the 

Bone;  3.  Middle  Turbinated  Bone  of  Eth-  nacal  no  in +17-  TVi^ir 
moid;  4.  Lower  Turbinated  Bone;  5.  Fifth 

Nerve.  come  to  the   surface 

of  the  mucous  membrane  as  the  finest  kind  of  threads, 
and  the  air,  sniffed  into  the  nostrils,  brings  odorous  par- 
ticles which  touch  these  tiny  fibres,  and  the  impression 
is  carried  by  them  to  the  brain.  The  two  olfactory  nerves 
in  1,  Fig.  69,  look  like  little  horns.  They  extend  from 
the  large  brain  mass  along  the  under  side  of  the  cere- 
brum till  they  reach  a  bone  just  above  the  nasal  cavity. 
Here  they  widen  out  into  two  bulbs  (Figs.  35,  74).  The 
bone  is  full  of  fine  holes,  like  a  sieve,  and  through  these 
holes  go  multitudes  of  fibrous  branches  from  the  bulb. 
Then  their  filaments  spread  over  the  mucous  membrane 
of  the  nose. 

The  nasal  cavity  is  divided  into  two  parts  by  the 
vomer,  or  ploughshare  bone  (Fig.  5),  and  the  outside 
walls  of  each  cavity  are  formed  of  bones  that  are  exceed- 
ingly curved  and  twisted.  By  covering  these  twisted 
bones  the  mucous  membrane  gets  a  great  extent  of  sur- 
face (Fig.  35),  and  consequently  the  smell  nerve  has 
greater  expansion.  In  order  that  a  substance  may  be 
smelled,  it  must  be  in  the  form  of  gas,  or  of  particles  fine 
enough  to  float  on  air:  there  must  be  a  draft  of  air,  and 

9— P 


132  PHYSIOLOGY. 

the  mucous  membrane  must  be  moist.  We  sniff  in  order 
to  make  the  particles  strike  sharply  on  the  ends  of  fila- 
ments. 

There  are  great  personal  differences  with  regard  to  taste 
and  smell.  The  use  of  tobacco,  alcoholic  drinks,  highly 
spiced  food,  and  many  drugs,  deaden  these  nerves  and 
destroy  their  function.  Smell  and  taste  can  be  culti- 
vated. In  large  tea  houses  there  are  people  called  tasters, 
who  have  such  delicacy  of  perception  that  they  can 
classify  the  many  various  chops  by  taste  and  smell. 

Hearing. — Touch,  taste,  and  smell  deal  with  solids, 
liquids,  and  gases;  but  whatever  the  material  is,  it  comes 
directly  in  contact  with  the  nerve  or  with  a  thin  skin  just 
over  it.  Hearing  and  sight  are  different.  The  ear  and 
the  eye  deal  with  objects  that  never  touch  them,  and 
their  nerves  are  shut  so  far  from  the  outside  world  that 
impressions  which  reach  them  must  pass  through  many 
fluids  and  tissues. 

It  is  supposed  that  the  object  that  gives  sound  or  color 
jars  the  air,  and  the  waves  are  carried  along  till  they 
reach  the  nerves  that  convey  the  impressions  to  the  gray 
cells,  some  of  which  recognize  sound,  and  others  perceive 
color  and  shape.  The  eye  and  the  ear  are  the  most  com- 
plex and  the  best  protected  organs  of  the  body. 

The  organ  of  hearing  is  made  of  so  many  parts  that 
it  is  easiest  studied  in  three  divisions:  the  external, 
middle,  and  internal  ear. 

The  External  Ear. — The  part  on  the  outside  of  the 
head,  which  is  generally  called  the  ear,  is  made  mainly 
of  cartilage,  and  it  is  of  less  importance  than  any  other 
part.  Many  animals  that  hear  well  have  no  visible  ears. 
Try  to  find  a  chicken's  or  canary  bird's  ears.  Do  you 
think  you  can  hear  better  than  a  bird?  The  cartilage 
part  of  our  ears  is  a  portion  of  the  external  ear.  It  is 


SPECIAL  SENSES. 


133 


II 


FIG.  75  (Copied).  Ear. — I.  Diagram  of  Ear:  6.  Concha;  ra.  Auditory 
Canal  (External),  d.  Tympanic  Membrane;  t.  Tympanic  Cavity;  e. 
Eustachian  Tube  (Middle),  s.  Semi-circular  Canals;  c.  Cochlea,  or 
Helix  (Internal).  /.  Styloid  Process  of  Temporal  Bone;  p.  Petrous 
Bone. 

II.  a.  Malleus;  (h.  Handle;)  b.  Incus:  (o.  Orbicular  Bone;)  c.  Stapes. 

{a.  Bony   wall; 
b.  Spiral    par- 
titions. 

IV.  r.  Tympanic  Ring  of  Temporal  Bone ;  a,  6,  c,  as  in  II. ;  d.  Mem- 
brana  Tympani. 


twisted  and  spread  out,  so  as  to  give  much  surface  for 
the  collection  of  sounds. 

A  person  who  is  hard  of  hearing  will  put  his  open  hand 
back  of  the  outer  ear  to  still  further  extend  the  surface. 
He  is  trying  to  make  his  ears  large.  This  cartilage  of  the 


134  PHYSIOLOGY. 

ear   is  covered  with   skin,  and  moved  by  a   few   small 
muscles. 

The  other  part  of  the  external  ear  is  called  the  audit- 
ory canal  (Fig.  75, 1.  m).  It  is  a  short  tube  of  bone  lined 
with  skin,  and  you  will  recognize  it  as  the  opening  of  the 
ear.  It  is  furnished  with  some  stiff  hairs,  and  some  oil 
glands  that  secrete  ear  wax.  The  hairs  and  the  bitter 
wax  keep  dust  and  insects  out. 

Middle  Ear. — The  external  is  separated  from  the  in- 
ternal ear  by  a  small,  tense  membrane,  called  the  ear 
drum,  or  tympanic  membrane  (Fig.  75, 1.,  IV.  d).  It  looks 
something  like  the  skin  stretched  across  the  head  of  a 
drum.  Because  of  this  membrane,  the  middle  ear  is 
called  the  drum  of  the  ear.  In  this  part  there  are  three 
dainty  little  bones.  They  are  the  smallest  bones  in  the 
body.  They  are  fastened  together,  and  extend  as  a  chain 
from  the  drumhead  to  the  opening  of  the  internal  ear. 
One  looks  like  a  stirrup,  and  the  others  are  supposed  to 
look  one  like  a  hammer,  and  the  other  like  an  anvil,  but 
the  resemblance  is  not  very  close  (Fig.  75,  II.  a,  6,  c). 
Small  as  they  are  (and  the  figure  gives  them  larger  than 
the  natural  size),  they  have  their  own  tiny  cover,  liga- 
ments, muscles,  nerves,  and  blood  vessels. 

There  is  a  tube  extending  from  the  middle  ear  to  the 
throat  (Fig.  75, 1.e).  It  is  for  the  entrance  of  air.  The 
mucous  membrane  that  lines  the  throat  extends  into  the 
ear,  and  when  a  person  has  a  cold  this  membrane  gets 
inflamed  and  swollen,  the  tube  is  closed,  and  hearing 
becomes  difficult.  The  bony  wall  between  the  middle 
and  inner  ear  has  two  openings,  called  little  windows, 
that  are  covered  by  membrane.  The  stirrup  rests  against 
ene  of  these. 

Internal  Ear. — The  internal  ear  is  peculiar  and  com- 
plicated. It  has  three  canals,  called  semi-circular  canals, 


SPECIAL  SENSES.  135 

carved  out  of  the  bone  (Fig.  75,  III.),  and  a  coiled  up 
part  called  helix,  or  snail  shell,  and  a  small  space  that  is 
nearest  the  middle  ear,  called  vestibule.  All  these  parts 
are  hollowed  out  of  the  hardest  bone  in  the  body,  a  por- 
tion of  the  temporal  bone,  and  you  can  best  understand 
their  minuteness  by  knowing  that  this  portion  of  the 
temporal  bone  is  but  little  over  an  inch  long. 

Inside  the  canals  there  is  a  liquid;  within  the  liquid 
there  is  a  membranous  tube,  running  the  whole  length 
of  the  canals,  and  in  places  it  is  dilated.  The  mem- 
branous tube  contains  another  liquid,  in  which  there  are 
some  bones  so  fine  as  to  be  called  ear  sand,  and  also 
some  filaments  of  the  nerve  of  hearing.  Other  filaments 
spread  over  the  spiral  plates  of  the  snail  shell.  The  use 
of  every  part  of  this  complicated  organ  of  hearing  is  not 
well  understood. 

It  is  supposed  we  hear  in  the  following  manner:  The 
tympanic  membrane  is  made  tense  or  lax  by  muscles. 
Sound  waves  strike  it,  and  it  vibrates;  the  motion  is  car- 
ried by  the  small  bones  that  touch  it  to  the  window  of  the 
internal  ear;  here  the  fluid  outside  and  inside  the  bags  is 
set  in  motion,  the  ear  sand  is  jarred  and  beats  against  the 
nerve  filaments,  and  the  impression  is  carried  by  the 
nerves  to  the  brain.  Other  jars  are  taken  up  by  the 
filaments  in  the  snail  shell.  And  in  this  way  the  brain 
becomes  conscious  of  sounds. 

The  Eye. — Notice  how  the  optic  nerves  start  from  the 
brain  (2,  Fig.  69).  They  look  like  a  little  sawbuck. 
Fig.  76  shows  how  one  enters  the  eyeball  like  a  thick  cord. 

Protectors. — Feel  the  bones  around  your  eye.  They 
form  the  orbital  cavity,  and  their  edges  stand  out  just  far 
enough  to  protect  the  eye  without  interfering  with  sight. 
The  eyebrows  are  arranged  so  as  to  keep  perspiration 
from  rolling  down  from  the  forehead  into  the  eyes.  The 
eyelashes  keep  out  dust,  and  the  eyelids  serve  as  live 


136 


PHYSIOLOGY. 


curtains  that  close  them- 
selves when  the  light 
is  too  strong,  or  any 
danger  threatens 
the  eyes.  See  h^w 
quickly  any  one 
winks  if  you 
make  believe  to 
strike  his  face. 
If  a  bit  of  sand 
gets  into  the  eye  how 
it  hurts,  and  how 
soon  the  eyes  are 
filled  with  tears. 
They  flow  over  the 
eyeball  and  try  to 
wash  away  the  offending  particle.  There  are  tear  glands 
connected  with  each  eye.  They  are  situated  under  the 
upper  eyelid  at  its  outer  side,  and  they  make  tears  ( Fig. 
77).  The  fluid  they  secrete  flows  across  the  eyeball  and 
enters  a  little  hollow  at  the 
inner  corner  of  the  eye. 
Then  it  finds  its  way  by 
the  tear  duct  (Fig.  77) 
into  the  nasal  cavity. 
That  is  the  ordinary 
way,  for  tears  are  being 

secreted  all  the  time  to  keep  ~9^^jgj^^ff--'  •  -"/  j' 

the  eyes  clear  and   bright.  '    /   / 


FIG.  76.  Horizontal  section  of  Right  Eye- 
ball. Coats:  1.  Sclerotic;  2.  Choroid;  3. 
Retina.  4.  Optic  Nerve;  5.  Cornea;  6.  Iris. 
Humors:  7.  Aqueous;  8.  Crystalline  Lens; 
9.  Vitreous  Humor.  10.  Ciliary  Process;  11. 
Ligament;  12.  Pupil;  13.  Blind  spot. 


But     when     a 
weeps,  the  tear 


person 
glands 


give    him 
than    the 


more  tears 
canals  can 
carry  away,  and  they 
overflow  the  lower  eye- 


FIG.  77  (Copied).  Eyeball  and  some  of 
its  appendages. — 1.  Tear  (Lachrymal} 
Gland;  2.  Tear  (Lachrymal)  Sac  and 
Nasal  Duct,  showing  two  small  canals, 
an  upper  and  a  lower,  leading  into  sac. 
Openings  of  Oil  Glands  shown  as  dots 
along  lower  Eyelid.  *  Shows  opening 
to  lower  Lachrymal  Canal. 


SPECIAL  SENSES.  137 

lid.  The  lids,  the  eyebrows,  and  the  lashes,  the  edges  of 
orbit,  and  the  tears  are  only  appendages  to,  or  protectors 
of,  the  eye  proper. 

The  eyeball  is  the  essential  organ.  It  is  a  dense  hol- 
low ball  filled  with  liquid  or  semi-liquid  materials.  It 
has  (Fig.  76): 


THREE    COATS. 


Sclerotic :  white,  outside. 
Choroid :  dark,  middle. 
Retina :  nerve,  inside. 


THREE    HUMORS. 


Aqueous :  in  front,  watery. 
Vitreous :  in  back,  jelly-like. 
Crystalline  lens :  between  thei 


solid. 

First  Coat. — The  outer  coat  forms  the  white  of  the 
eye,  and  also  the  transparent  part  in  front,  called  the 
cornea  (5,  Fig.  76).  The  stiffness  of  its  walls  gives  shape 
to  the  eyeball.  This  coat  has  no  nerves,  therefore  no  feel- 
ing, and  can  be  cut  without  paining  the  eye.  Then,  what 
hurts  so  when  sand  gets  in? 

It  is  the  fine  mucous  membrane  that  lines  the  eyelids 
and  extends  over  the  front  of  the  eyeball.  It  is  full  of 
nerves  and  blood  vessels,  and  gets  bloodshot  when  gritty 
particles  irritate  it.  Bloodshot  means  that  the  tiny,  in- 
visible blood  vessels  get  so  full  of  blood  from  the  irrita- 
tion that  they  can  be  seen. 

Second  Coat. — The  middle,  or  choroid,  coat  is  dark 
colored,  because  it  is  full  of  pigment.  It  has  many  ves- 
sels. Notice  the  colored  part  of  your  eye.  It  is  a  thin, 
circular,  muscular  band  fastened  by  its  outer  edges  to  the 
choroid  coat.  It  is  called  the  iris,  and  gives  color  to  differ- 
ent eyes.  The  hole  in  the  center  of  the  iris  grows  larger 
if  you  go  from  a  light  to  a  dark  room,  and  smaller  if 
you  go  into  strong  light.  It  is  called  the  pupil  of  the  eye. 

In  a  cat  the  iris  is  a  straight  up  and  down  slit  in  the 
daytime.  The  iris  is  able  to  change  shape,  because  it 
has  two  sets  of  muscular  fibres — one  ring-like,  and  the 


138  PHYSIOLOGY. 

other  radiating.  By  its  contraction  or  relaxation  the  right 
amount  of  light  is  admitted  to  the  eye.  The  pigment  of 
the  choroid  coat  is  supposed  to  absorb  any  light  that  gets 
into  the  eye  and  that  does  not  fall  on  the  optic  nerve,  and 
thus  keeps  the  image  from  being  blurred. 

Third  Coat. — The  internal  coat  is  the  expansion  of 
the  nerve  of  sight,  and  it  forms  a  network  of  fibres  and 
curious  cells,  rods,  and  cones  that  spreads  over  the  dark 
choroid.  It  is  called  the  retina.  This  is  the  part  that 
receives  impressions  of  color  and  shape,  and  transmits 
them  to  the  brain.  The  retina  is  the  essential  part  of 
the  organ  of  sight  for  which  all  the  other  parts  are  made. 

Sight  Spot. — There  are  two  important  spots  con- 
nected with  the  retina.  One  is  at  the  back  of  the  eye- 
ball, directly  opposite  the  middle  of  the  cornea.  It  is 
called  the  yellow  spot,  and  is  the  most  sensitive  portion 
of  the  retina.  It  is,  more  than  all  other  parts  of  the  eye, 
the  sight  spot. 

The  Blind  Spot. — The  other  spot  is  just  its  opposite 
in  being  entirely  blind.  It  is  on  the  nasal  side  of  the 
eyeball,  a  little  distance  from  the  yellow  spot.  This  is 
where  the  optic  nerve  enters  the  eyeball.  There  is  plenty 
of  nerve  material  there,  but  it  has  not  the  right  arrange- 
ment. 

Power  of  sight  does  not  seem  to  depend  on  the  presence 
of  nerve,  but  upon  its  arrangement.  It  is  said  that  the 
optic  nerve  is  quite  as  blind,  or  as  incapable  of  carrying 
impressions  of  light,  as  any  nerve  of  the  body,  when  it 
does  not  have  the  cone  and  cell  arrangement. 

Experiment. — You  can  easily  prove  that  there  is  a 
blind  spot.  Hold  your  pencil  at  arm's  length  horizontally 
before  your  eyes.  Shut  one  eye;  with  the  other  eye  look 
fixedly  at  the  end  of  the  pencil  opposite  the  closed  eye. 
Both  ends  can  be  seen.  Now  draw  the  pencil  nearer. 


SPECIAL  SENSES.  139 

There  comes  a  place  where  you  can  see  only  the  end  upon 
which  your  look  is  fixed.  On  bringing  the  pencil  nearer 
still,  the  lost  end  comes  again  into  view.  This  means  that 
in  altering  the  position  of  the  pencil,  the  image  of  the  end 
that  becomes  invisible  changes  its  position  on  the  retina, 
and  in  moving  along  comes  before  the  blind  spot,  and 
thus  disappears.  Later,  when  it  has  passed  this  spot, 
it  is  seen  again. 

The  same  experiment  may  be  made  by  holding  this 
page  at  arm's  length,  and  looking  at  the  letters  below  in 
a  similar  way. 


B 


Humors  of  the  Eye. — The  humors  of  the  eye  do  not 
occupy  equal  spaces,  and  they  are  of  different  consist- 
ency. In  the  little  room,  which  has  the  cornea  in  front 
and  the  iris  and  crystalline  lens  behind,  is  found  a  thin, 
watery  liquid,  called  aqueous  humor  (7,  Fig.  76). 

The  crystalline  lens  is  almost  too  solid  to  be  called  a 
humor.  It  is  clear  like  glass,  and  tough  like  stiff  jelly, 
so  that  it  retains  its  shape  when  removed.  It  can  be 
removed  from  the  eye  of  a  fish  or  a  beef.  A  beef's  eye 
is  a  good  study,  being  large  enough  to  show  clearly  all 
the  parts. 

The  cornea  helps  adapt  rays  to  enter  the  eye.  The 
function  of  the  crystalline  lens  is  to  change  the  direction 
of  the  rays.  This  is  done  by  altering  its  shape  by  means 
of  the  ligaments  which  hold  it  in  place  (11,  Fig.  76).  It 
stiffens  with  age,  so  that  elderly  people  cannot  see  well. 

The  largest  part  of  the  eyeball  is  filled  with  a  jelly- 
like  substance  called  vitreous  humor,  that  remains  stiff 
for  only  a  short  time  after  it  is  taken  out. 

Muscles. — There  are  a  number  of  small  voluntary 
•muscles  attached  to  the  eyeball  and  the  orbital  cavity, 
which  pull  the  eyeball  and  enable  a  person  to  look  in 


140 


PHYSIOLOGY. 


many  directions.  Will  to  look  up,  and  the  eyeball  is 
directed  upward;  to  look  down,  and  it  is  pulled  down- 
ward. The  rolling  of  the  eyes  is  caused  by  a  number 
of  different  muscles  acting  in  turn ;  and  because  the  eye- 
ball can  so  move,  its  socket  or  cavity  is  called  the  orbit. 


Names  of 
Senses. 

Touch  . 


Smell 


Taste  . 


Organs. 
.  Skin. 

.  Nose. 


SPECIAL    SENSES. 

Parts. 

f  Papillae 

\  Touch  Corpuscles  .  .  . 


Filaments 
Bulb.  . 


f  Taste  Bulbs 

Tongue.  <j  f  circuravallate 


*  Papillae. 


Sight.  .  Eyeball. 


Hearing  .  .  Ear. 


Coats 


Humors 


External 


Middle 


]  Fungiform 
I  Filiform   . 


Sclerotic        (includes 

Cornea) 

Choroid  (includes  Iris 

and  Pupil) 

Retina 

f  Vitreous 

•j  Aqueous 

[  Crystalline 

Concha 

Auditory  Canal  .... 

(  Tympanic  Membrane, 
f  Incus  .... 
Bones.  \  Malleus  .  .  . 
•{                (  Stapes .... 
Windows,    or     Fora- 
mina   

Eustachian  Tube  .  .  . 


Nerves. 
Sensation. 

Smell,     or 
Olfactory. 

Taste, 
or    Gusta- 
tory. 


Sight,  or 
Optic. 


Vestibule 


Labyrinth. 


Cochlea,  or  Helix  .  .  . 
Filaments  ....... 


Hearing, 

or 
Auditory. 


SPECIAL  SENSES.  141 

THOUGHT,  OR  OBSERVATION,  QUESTIONS. 

Do  any  nerves  of  special  sense  start  from  the  spinal  column? 

How  do  sensory  and  smell  nerves  differ  in  termination  ? 

If  dry  goods  are  not  all  wool,  what  is  one  way  to  find  it  out? 

Can  you  think  of  any  reason  for  the  projections  on  the  tongue  ? 

How  does  the  sense  of  smell  act  as  a  protector? 

Does  the  size  of  the  nose  have  anything  to  do  with  the  acuteness 
of  smell? 

What  is  the  reason  that  some  people  enjoy  scents  and  tastes  that 
disgust  others? 

Why  are  our  senses  less  acute  than  those  of  savages  ? 

What  does  it  mean  "  to  strain  one's  ears  to  hear  ? " 

What  is  the  reason  that  the  howling  of  a  dog  annoys  us  while  we 
are  trying  to  hear  music  ? 

Why  do  some  dogs  howl  when  they  hear  church  bells  ring  ? 

When  a  stone  is  thrown  into  a  lake,  what  happens  to  a  ripple 
before  it  goes  a  mile  ? 

Can  you  see  any  relation  between  this  and  the  fact  that  you  can- 
not hear  a  person  who  is  speaking  a  mile  away  ? 

How  many  colors  can  be  found  in  the  eye  ? 

What  part  of  the  eye  is  nerve,  and  what  muscle? 

Are  there  blood  vessels  inside  the  eyeball  ? 

Are  there  any  nerves  in  the  sclerotic  coat  ? 

What  is  the  relative  size  of  the  humors  ? 

What  enables  the  optic  nerve  to  carry  impressions  of  light  ? 

Are  there  any  gray  cells  in  the  eye  ? 


142  PHYSIOLOGY. 

MEMORY  QUESTIONS. 

I. 


CHAPTER  1. 

Cells. — Define  cell.  Can  you  see  one?  How  do  people  know 
cells  exist?  Are  they  all  of  one  shape?  Draw  four  shapes.  Name 
five  kinds.  What  do  they  contain?  Are  they  abundant?  What  do 
they  build? 

Tissues. — What  is  a  tissue?  Name  and  locate  five  kinds.  What 
is  the  difference  between  skin  and  bone?  How  do  you  know? 
Name  a  characteristic  of  cartilage.  Where  is  it  found,  and  what 
is  its  common  name?  What  is  the  relative  position  of  tissues  in 
the  thumb?  Which  is  outside?  Which  is  hardest?  Which  is 
cord-like  ?  What  is  a  common  name  for  muscle  ?  What  is  it  called 
when  we  eat  it? 

Fluids. — What  makes  cheeks  and  lips  red?  What  other  fluid  do 
you  know? 

Organs. — Define  an  organ.  What  is  it  made  of?  Name  an  organ 
of  the  head.  Name  an  organ  of  the  trunk.  Is  there  anything  but 
tissue  in  an  organ?  What  kind  of  an  organ  is  the  hand?  What  is 
the  use  of  the  heart?  Name  paired  organs.  Name  single  organs. 

Systems. — Define  system.  What  organs  besides  the  heart  make 
the  circulating  system?  How  is  a  person  poisoned?  WTiat  system 
does  food  affect?  What  are  its  parts?  Why  does  the  head  ache 
after  eating  bad  food  ?  What  is  health  ?  What  is  disease  ? 

The  Head. — What  is  the  shape  of  the  bony  part  of  the  head? 
What  are  the  hollows  of  the  head  called?  Where  is  the  orbital 
cavity?  How  does  the  oral  differ  from  the  cranial  cavity?  What 
organ  is  in  the  oral  cavity?  What  cavities  look  forward?  Which 
is  the  largest?  Do  any  look  any  other  way?  What  covers  the  nasal 
cavity?  Is  it  entirely  shut?  Which  cavities  have  doors?  Is  any 
cavity  entirely  shut ?  What  is  the  use.  of  cavities?  What  tissues 
cover  the  head?  Where  are  blood  vessels  seen?  Where  can  car- 
tilage be  felt?  What  is  nearly  as  flexible  as  cartilage?  Where  can 


MEMORY  QUESTIONS.  143 

the  most  muscle  be  found?    How  do  you  know  there  is  bone  and 
skin  to  the  head?    What  is  the  use  of  the  bony  box  of  the  head? 

The  Trunk. — How  does  the  trunk  cavity  differ  from  the  head 
cavity?  Name  the  parts  of  the  trunk  cavity.  What  is  the  trunk 
often  called?  How  do  you  know  the  upper  part  of  the  trunk  moves? 
How  does  the  upper  part  differ  from  lower?  What  is  there  peculiar 
at  back  of  the  trunk?  Is  the  backbone  one  bone?  Locate  the  ribs. 
What  is  the  shape  of  the  ribs?  What  bones  are  they  joined  to? 
Why  do  the  ribs  move  ? 

Extremities. — What  is  the  common  name  for  extremities?  Name 
parts  of  the  leg.  Name  parts  of  the  arm.  Compares  the  arm  with 
the  leg.  How  are  tissues  arranged  in  a  thumb  ?  Where  can  the 
arrangement  be  seen  ?  Why  are  we  able  to  bend  our  hands  ?  What 
tissues  generally  form  a  joint?  How  does  muscle  end?  Where  are 
the  nails?  What  are  the  cords  of  a  chicken's  drumstick?  Where 
is  the  bone  ?  What  is  the  thick  mass  at  the  upper  end  ?  What  do 
head,  trunk,  and  limbs  form?  Of  what  is  each  part  composed? 


CHAPTER  2. 

Of  any  bone  give:  Name,  position,  use,  class,  color,  structure, 
size,  shape,  composition,  cover,  and  most  important  characteristic. 
Why  are  bones  brittle? 
What  makes  bones  hard? 
How  many  classes  of  bones  are  there? 
Name  ten  long  bones. 
How  does  blood  get  inside  of  bones? 
Where  are  the  ligaments  found? 
Which  joint  admits  of  freest  motion? 
What  is  the  reason  joints  do  not  creak? 
How  do  ribs  differ  in  their  attachment  to  the  breast  bone? 
Locate  and  give  use  of  suture,  mastoid,  cartilage. 


CHAPTER  3. 

Of  any  muscle  give:  Name,  position,  use,  class,  color,  size,  shape, 
composition,  structure,  cover,  and  most  important  characteristic. 
What  kind  of  muscle  has  spindle-shaped  cells? 


144  PHYSIOLOGY, 

CHAPTER  4. 

Of  any  part  of  the  skin  give :  Name,  position,  use,  class,  color, 
shape,  parts,  composition,  structure,  and  chief  characteristic. 

How  does  mucous  membrane  differ  from  skin  ? 

What  covers  gums;  roof  of  mouth;  inside  of  eyelids;  inside  of 
stomach;  hands;  cheeks? 

Why  does  it  not  hurt  to  cut  hair  and  nails? 

Why  do  the  eyes  of  white  rabbits  look  pink? 

What  effect  has  hard  work  on  the  hands? 

What  happens  if  poison  is  rubbed  on  the  skin? 

Why  does  a  knife  slip  off  a  hair  held  by  the  root? 

Locate  and  give  use  of  papillae ;  of  pigment  layer. 

What  is  the  difference  of  function  in  oil  and  in  perspiratory 
glands? 

How  can  "  in  visible"  perspiration  be  shown? 

Is  perspiration  an  excretion  or  secretion? 

What  becomes  of  all  the  water  brought  to  the  surface  by  per- 
spiratory glands? 

What  effect  has  dampness  on  curly  hair? 

Does  hair  sunburn? 

How  does  fright  cause  hair  to  "  stand  on  end? " 


CHAPTER  5. 

Of  any  organ  give:  The  name,  position,  use,  class,  color,  size, 
shape,  structure,  cover,  and  most  important  characteristics. 

Of  any  juice  give :  Color,  uses,  location,  and  gland. 

What  is  the  advantage  of  length  and  convolution  in  the  food 
canal? 

For  what  two  reasons  does  food  have  to  be  chewed? 

What  kind  of  a  lining  has  the  food  canal? 

How  do  the  folds  of  the  stomach  differ  from  those  of  the  intes- 
tines? 

Is  the  stomach  above  or  below  the  diaphragm? 

If  teeth  are  not  sensitive,  why  do  we  say  a  tooth  aches? 

What  causes  bleeding  when  teeth  are  pulled  ? 

Name  the  hollows  from  which  hair,  teeth,  and  nails  grow. 

Do  salivary  glands  make  secretions  or  excretions  ? 


MEMORY  QUESTIONS.  145 

What  is  the  difference  of  direction  of  blood  and  bile  in  the  liver? 
What  is  the  difference  in  the  composition  of  blood  and  bile? 

What  effect  has  too  rapid  eating  on  starchy  food? 

Name,  in  order,  the  glands  of  digestion. 

What  part  of  the  food  canal  is  widest? 

What  is  a  liver  lobule? 

In  how  many  ways  do  bones  differ  from  teeth  ? 

Name  a  difference  of  function  and  one  of  appearance  between 
incisors  and  molars. 

How  does  chyme  differ  from  chyle  in  looks,  locality,  and  compo- 
sition ? 

Into  which  part  of  the  food  canal  does  the  greatest  variety  of 
digestive  juices  empty? 


CHAPTER  6. 

Of  any  organ  give:  Name,  structure,  use,  position,  connection 
with  other  organs,  and  chief  characteristic. 

Of  any  fluid  give  :  Color,  structure,  use. 

Name  two  differences  between  veins  and  arteries. 

What  is  the  difference  between  heart  cover  and  heart  material? 

Is  heart  muscle  voluntary? 

Name  three  differences  between  tongue  and  heart  muscle. 

Into  what  part  of  the  heart  do  the  large  vessels  from  the  body 
enter? 

Of  what  color  is  the  blood  in  the  right  ventricle  ? 

What  is  its  color  in  the  left  lung? 

How  many  valves  has  the  heart  ? 

What  prevents  the  blood  from  falling  back  when  the  ventricle 
expands? 

Name,  in  order,  all  organs  the  blood  must  pass  through,  from  left 
ventricle  back  to  left  ventricle. 

What  effect  does  each  of  the  following  organs  have  on  the  blood : 
Lungs,  liver,  skin,  kidneys,  spleen? 

What  makes  the  blood  dark  when  it  comes  from  capillaries  ? 

From  what  organs  does  blood  come  to  enter  portal  vein  ? 

What  is  peculiar  about  portal  circulation?    Splenic  circulation  ? 

Where  does  the  blood  in  the  stomach  come  from  ? 

What  is  the  reason  there  is  a  blood  vessel  of  one  kind  going  to  an 
organ,  and  of  another  leaving  it? 


146  PHYSIOLOGY. 

Is  the  liver  an  organ  of  digestion  or  of  circulation? 
Locate  and  give  use  of  liver  cells,  of  valves,  of  pleura,  of  bile  cyst, 
of  lobule,  of  capillaries,  of  corpuscles. 

From  what  two  distinct  sources  does  blood  flow  into  the  liver? 
Where  does  it  go  when  it  leaves  it  ? 
What  is  the  difference  between  lymph  and  chyle  ? 
How  does  blood  differ.from  lacteal  material  ? 
Do  lacteals  ever  carry  lymph  ? 
Do  all  the  lymphatics  empty  into  the  left  subclavian  vein  ? 


CHAPTER   7. 

Of  any  organ,  or  part,  give :  Name,  position,  use,  color,  size,  shape, 
structure,  an4  chief  characteristic. 

Name  two  important  differences  between  air  tubes  and  blood 
vessels. 

Are  air  tubes  alike  throughout? 

What  is  the  advantage  in  the  shape  of  the  rings  of  the  trachea? 

What  harm  does  it  do  to  have  food  "go  the  wrong  way?  " 

What  two  organs  generally  keep  dust  out  of  the  lungs? 

Where,  besides  in  the  lungs,  is  there  transmission  by  osmose? 

Name  the  microscopic  organs  involved  in  respiration. 

What  causes  the  bad  odor  of  air  from  lungs? 

How  can  any  one  show  that  there  is  moisture  in  the  breath? 

What,  is  the  difference  between  breathed-in  and  breathed-outair? 

Are  the  false  vocal  cords  above  or  below  the  others? 

Is  the  vocal  membrane  stretched  from  side  to  side,  or  from  the 
front  backward? 

What  is  the  use  of  cartilage  in  the  windpipe  ? 

What  makes  the  difference  between  a  man's  and  a  woman's  voice  ? 


CHAPTER   8. 

Of  any  part  give:  Name,  position,  use,  class,  color,  size,  sjiape, 
structure,  cover,  relation  to  brain,  and  chief  characteristic. 

How  do  the  two  divisions  of  the  nervous  system  differ  in  function 
and  appearance? 


MEMORY  QUESTIONS.  147 

What  kind  of  nerve  matter  is  ruler,  and  which  organ  of  the  sys- 
tem rules  all  others? 

Where  in  the  body  is  the  greatest  amount  of  gray  matter? 

Is  there  more  than  one  cell  in  a  ganglion? 

What  is  the  use  of  so  many  coats  to  the  brain  ? 

Where  is  the  spinal  cord  thickest? 

What  kind  of  nerve  material  is  inside  the  spinal  cord? 

If  your  face  is  scratched,  what  kind  of  nerve  carries  the  impres- 
sion? Where  does  it  carry  it? 

How  is  the  nervous  system  so  well  protected?    Why? 

Why  is  a  hand  pulled  away  from  hot  things?  What  pulls  it? 
What  directs  the  pulling? 

What  nerve  directs  the  digestion  of  food  ? 

If  a  cut  is  deep  enough  to  bring  blood,  what  happens,  and  why? 

What  part  of  the  brain  controls  the  idea  of  love  of  country  ? 

What  part  of  a  man  tells  him  it  is  cowardly  to  strike  a  woman  ? 

What  is  the  difference  of  arrangement  of  gray  and  white  matter 
in  the  brain  and  in  the  spinal  cord? 

How  can  you  know  that  a  small  spot  on  the  hand  is  hurt  ? 


CHAPTER  9. 

Of  any  organ,  or  part,  give :  Name,  position,  use,  class,  color,  size, 
shape,  structure,  essential  or  non-essential  relations,  and  most  im- 
portant characteristic. 

Is  there  any  difference  between  nerve  material  in  the  optic  and 
the  sensory  nerve? 

Why  does  a  woman  when  ironing  place  a  hot  iron  near  her 
cheek  instead  of  her  hand  to  learn  whether  it  is  hot  enough  ? 

What  is  " feeling  pain,"  and  where  is  it  felt? 

Wlby  do  people  sometimes  say  an  article  tastes  good  when  it  has 
no  taste? 

Which  special  sense  has  a  nerve  bulb? 

With  what  condition  of  matter  does  each  sense  deal? 

What  part  of  the  hearing  organ  is  pounded,  and  why? 

Which  can  be  shaken  most,  a  bag  fastened  to  the  ground  or  one 
hung  in  water? 

In  what  part  of  the  ear  are  there  some  bags? 

Why  cannot  some  people  tell  one  tune  from  another? 
10— P 


148  PHYSIOLOGY. 

Why  do  not  we  consider  the  sounds  on  Chinese  instruments  as 
musical  as  those  produced  by  our  own  orchestras? 
What  keeps  perspiration  from  running  into  the  eyes  ? 
What  use  have  tears  except  to  express  emotion  ? 
Why  does  an  iris  contract? 

How  do  the  two  spots  on  the  retina,  differ  in  action  and  position  ? 
What  is  the  hardest  part  of  the  eye?    Where  is  it? 
What  hurts  when  dust  gets  in  the  eye  ? 
What  happens  besides  the  hurt? 
How  does  an  eye  get  bloodshot? 


PART  II. 


HYGIENE 


II. 


CHAPTER  1. 

GENERAL    HYGIENE. 

Health  is  a  condition  of  the  body  in  which  all  its  parts 
work  well.  To  keep  healthy,  proper  time  and  attention 
should  be  paid  to  getting  good  food,  plenty  of  rest,  pure 
air,  daily  exercise,  suitable  clothing  and  baths,  and  per- 
fectly clean  and  sweet  surroundings. 

Every  one  should  understand  the  conditions  necessary 
for  keeping  well,  for  a  person  who  obeys  hygienic  laws 
is  less  liable  than  unclean  and  intemperate  people  to 
contagious  diseases,  and  he  can,  with  care,  keep  from 
suffering  from  dyspepsia,  rheumatism,  and  many  of  the 
every-day  diseases  that  torment  mankind. 

People  suffer  from  breaking  these  laws,  even  when  they 
are  ignorant  of  the  laws  that  are  broken.  If  hygiene  is 
neglected  either  by  an  individual  or  a  community,  some 
one  has  to  pay  the  penalty  in  pain  or  disease.  A  physical 
debt  is  never  outlawed. 

Disease  is  a  disorder  of  one  or  more  of  the  organs  of  the 
body,  caused  by  breaking  the  laws  of  hygiene.  Catching, 
or  contagious,  diseases,  such  as  cholera,  diphtheria,  small- 
pox, and  typhoid  fever,  are  penalties  paid  for  allowing 
filth  to  accumulate,  and  the  innocent  suffer  with  the 
guilty.  Some  diseases  occur  to  an  individual  through 
his  own  carelessness  or  ignorance,  and  some  others 
through  faults  of  his  parents, 


152  HYGIENE. 

Children  are  oftener  weak  and  diseased  because  they 
are  born  unhealthy  than  because  they  are  neglected  after 
their  birth.  The  children  of  people  given  to  stimulants, 
narcotics,  or  any  form  of  intemperance,  are  apt  to  be  irri- 
table, and  have  a  tendency  toward  excess  of  various 
kinds.  The  gray  nerve  cells  in  children  of  drunkards  are 
often  so  disordered  that  their  sense  of  right  and  wrong  is 
nearly  destroyed.  Frequently  such  children  are  weak- 
minded,  or  idiotic,  or  born  with  a  craving  for  liquor  which 
they  cannot  control.  On  the  other  hand,  children  of 
healthy  and  temperate  people  are  apt  to  inherit  strong 
bodies  and  sound  minds. 

This  resemblance  of  children  to  parents  is  called  hered- 
ity, or  inheritance.  As  children  inherit  the  same  kind 
of  eyes,  shape,  complexion,  and  gait  as  their  parents,  so, 
also,  they  inherit  their  diseases  or  strong  constitutions. 
But  even  inherited  tendencies  can  be  overcome  by  care. 

The  natural  powers  of  resistance  are  so  different  in 
different  people  that  no  set  of  rules  will  apply  to  all  indi- 
viduals, but  obeying  the  laws  of  hygiene  will  generally 
insure  health.  It  is  not  the  grown  people  with  their  bad 
habits  formed  and  their  diseases  settled  on  them  who  can 
be  most  helped  by  complying  with  simple  hygienic  laws. 
It  is  the  children  who  are  building  up  their  bodies  and 
forming  habits.  Growing  people  cannot  properly  eat, 
drink,  and  wear  many  things  that  are  safe  for  grown 
people. 


HYGIENE  OF  THE  BONES.  153 

CHAPTER  2. 

HYGIENE    OF    THE   BONES. 

The  skeleton  is  not  so  liable  to  injury  and  disease  as 
the  softer  parts  of  the  body.  After  the  bones  are  full 
sized  and  hardened,  proper  food,  exercise,  and  warmth 
will  keep  them  in  good  condition. 

Children's  Bones. — Children's  bones  being  more  flex- 
ible, are.  apt  to  bend  and  grow  out  of  shape  if  subject  to 
great  strain.  For  this  reason  children's  work  should  be 
light.  A  young  child  should  never  carry  heavy  babies, 
or  loads  of  coal  or  water,  for  there  is  great  danger  of  twist- 
ing the  spinal  column,  rounding  the  shoulders,  and  mak- 
ing the  child  deformed  for  life.  This  is  especially  to  be 
avoided  in  delicate  and  quick-growing  children. 

Habits  to  Avoid. — Examine  the  following  list  of  bad 
habits  and  see  if  you  have  any  of  them  to  correct: 

Sitting  on  one  foot. 

Standing  on  one  foot. 

Stooping  over  while  working  or  studying. 

Lifting  or  carrying  heavy  loads. 

Always  carrying  school  books  on  one  arm,  or  doing 
anything  else  that  lifts  one  shoulder  higher  than  the  other. 

Holding  the  head  bent  forward. 

Throwing  the  shoulders  forward,  thus  making  "  round 
shoulders." 

Sleeping  on  high  pillows  so  that  the  back  is  curved. 

Sitting,  standing,  or  lying  with  the  back  arched. 

Pulling  at  fingers  to  "crack"  the  joints. 

Sitting  at  desks  that  are  too  low. 

Sitting  on  chairs  that  are  too  high. 

Wearing  tight  clothing. 

Sitting  on  the  spinal  column. 


154  HYGIENE. 

These  habits  pull  the  bones  and  ligaments  out  of  place 
and  the  result  is  hollow  chest,  crooked  back,  round 
shoulders,  or  some  other  distortion,  for  the  man  or 
woman.  A  child  can  do  a  great  deal  toward  growing  to 
be  a  straight  and  well  formed  man  or  woman,  but  care 
should  be  taken  by  parents  and  teachers  to  correct  lazy 
ways  of  sitting  and  walking,  and  to  have  desks  and 
chairs  that  will  not  strain  the  ligaments  or  in  any  way 
tend  to  get  the  child  out  of  proportion. 

Clothing. — Children  should  never  wear  tight  clothing 
or  garments  of  stiff  materials  that  keep  the  parts  of  the 
body  from  naturally  expanding  and  from  supporting 
themselves.  It  is  the  work  of  ligaments  to  hold  bones 
in  place,  and  when  tight  corsets  are  used  to  hold  up  the 
body,  they  weaken  the  natural  supports.  Tight  clothing 
also  crushes  in  the  ribs  and  makes  deformed  waists.  The 
clothing  should  be  loose,  and  of  a  fabric  warm  enough  to 
keep  the  body  from  bad  effects  of  sudden  changes  of  cli- 
mate, and  should  cover  the  entire  body.  Tight  shoes 
cramp  and  deform  the  feet  and  are  apt  to  give  an  awkward 
gait,  while  high-heeled  shoes  throw  the  .body  out  of  its 
natural  position  and  cause  displacement  of  organs. 

Food. — Growing  children  need  much  nutritious  food. 
Their  tissues  are  forming  so  fast  that  they  are  always 
hungry.  Lime  is  needed  for  making  bone,  and  home- 
made brown  bread  and  oatmeal  are  good  bone-making 
foods.  Milk  contains  some  of  the  same  substances  that 
are  found  in  bone,  besides  having  an  abundance  of  other 
tissue  makers. 

Broken  Bone. — Sometimes  a  bone  is  broken.  When 
this  occurs  the  strong  tendons  pull  so  hard  that  they 
make  the  jagged  broken  edges  slip  past  each  other,  and 
tear  the  soft  tissues.  If  the  accident  happens  when  there 


HYGIENE  OF  THE  BONES.  155 

is  no  doctor  near,  a  little  care  will  keep  the  bone  from 
doing  much  injury.  Keep  the  broken  limb  still.  If  it 
is  a  broken  arm,  make  a  sling  with  pocket  handkerchiefs, 
and  fasten  the  arm  in  it,  and  then  pin  the  sling  tightly 
to  the  dress  or  coat.  If  a  leg  be  broken  the  person  should 
lie  down  till  the  doctor  comes,  or  be  carried  to  the  doctor 
on  a  stretcher,  having  the  injured  leg  fastened  to  the  other 
to  prevent  jarring  the  bone  and  tearing  the  flesh. 

Sprains. — Sometimes  a  mis-step  wrenches  or  stretches 
a  ligament  or  tendon.  This  injury  is  called  a  sprain, 
and  is  generally  made  worse  by  one  of  the  small  bones,  as 
of  the  ankle  or  wrist,  being  pulled  out  of  place.  A  sprain 
is  generally  worse  than  a  broken  bone.  In  no  case  should 
a  sprained  part  be  used.  Rest  is  what  it  needs.  Band- 
age it  and  let  it  alone,  unless  it  is  so  serious  that  a  doctor 
has  to  take  charge  of  it. 

Diseases  of  Bones  and  Joints. — Sometimes  the 
membranes  of  the  joints  and  the  cover  of  the  bones 
become  inflamed  and  diseased  from  exposure  to  wet 
and  cold,  and  a  person  aches  all  over.  Sitting  in  a  draft 
when  overheated,  keeping  on  wet  shoes  and  clothing, 
result  sometimes  in  cold,  and  sometimes  in  rheumatism. 
Rheumatism  is  a  name  given  to  a  number  of  diseases  that 
affect  the  muscles  and  bones.  When  it  is  in  the  joint,  it 
is  an  inflammation  of  the  membrane  that  secretes  the 
fluid  for  oiling  the  joint,  and  the  disease  is  caused  by 
exposure  to  cold  and  wet,  and  neglect  of  hygienic  laws. 

Rickets  is  a  disease  of  children  that  comes  partly  through 
want  of  proper  food.  The  bones  are  not  strong  enough, 
the  head  is  generally  large,  and  the  child  is  feeble  and 
thin. 

Gout  is  a  disease  of  the  joints  that  may  be  inherited, 
or  may  be  brought  on  by  lead  poisoning,  by  drinking 
wine  and  malt  liquors,  or  by  large  consumption  of 
animal  food. 


156  HYGIENE. 

CHAPTER  3. 

HYGIENE    OF    THE    MUSCLES. 

Muscles  need  regular  rest  and  exercise.  Regularity  is 
one  of  the  first  laws  of  health.  Muscles  that  are  not 
used  become  small  and  useless,  while  muscles  that  are 
exercised  become  large  and  firm.  Exercise  also  causes 
the  heart  to  beat  faster  and  the  blood  to  flow  more  rap- 
idly, and  thus  it  quickens  the  action  of  all  organs.  Chil- 
dren naturally  take  all  the  exercise  they  need.  Active 
muscular  exertion,  such  as  running  and  jumping,  is  apt 
to  injure  older  persons,  but,  in  moderation,  is  good  for 
young  people.  In  excess  it  is  injurious.  If  a  child  jumps 
the  rope  till  she  falls  down,  or  another  lifts  such  heavy 
weights  that  he  sprains  his  back,  or  another  runs  or 
jumps  till  he  faints  away,  it  is  just  as  wrong  as  to  sit  or 
lounge  till  the  muscles  are  pale  and  flabby.  Each  excess 
has  its  penalty. 

Exercise. — There  are  many  forms  of  exercise,  but  all 
kinds  should  be  taken  out  of  doors,  or  with  doors  and 
windows  open.  Rowing,  swimming,  working  in  a  garden, 
horseback  riding,  and  light  gymnastics,  are  all  good  for 
people  who  study,  or  are  shut  up  many  hours  in  stores  or 
offices.  A  good  brisk  walk  of  an  hour  or  two  each  day  is 
a  health-giver  and  a  beautifier.  It  is  within  the  reach  of 
all,  and  one  of  the  best  ways  to  keep  the  body  in  good  con- 
dition. It  brings  into  play  many  muscles,  stirs  the  slug- 
gish blood,  drives  impure  air  from  the  lungs,  sends  a  glow 
over  the  skin,  stimulates  the  nerves,  and  brightens  the 
eyes  and  causes  the  brain  to  act  quicker  and  better.  An 
appreciation  of  nature  adds  much  pleasure  to  walking,  for 
when  the  brain  is  agreeably  employed  it  gives  tone  to  the 
whole  system. 


HYGIENE  OF  THE  MUSCLES.  157 

Best  of  Muscles. — Rest  is  as  necessary  as  exercise. 
Over  exertion  of  the  muscles  causes  aching  and  weari- 
ness, and  often  reacts  on  the  other  systems,  creating  seri- 
ous disturbances.  Athletes  and  gymnasts  who  develop 
their  muscles  to  the  fullest  extent  are  not  generally  long 
lived,  and  they  often  die  of  heart  disease.  Their  muscu- 
lar system  is  developed  at  the  expense  of  some  other  sys- 
tem. No  muscle  acts  on  forever.  All  parts  get  tired 
and  worn  out.  To  hold  the  arms  straight  out  from  the 
sides  for  ten  or  more  minutes  gives  aching  pains,  and  the 
arms  seem  to  grow  heavy  as  lead.  Digging,  running, 
playing  ball,  or  any  form  of  exercise,  when  too  long  con- 
tinued, becomes  torture.  Muscles  must  rest.  The  rest- 
ing time  for  the  voluntary  ones  is  generally  when  we  are 
asleep.  The  involuntary  ones,  having  a  special  work  to 
do,  rest  when  they  get  a  chance.  The  food  preparers  rest 
when  we  are  not  eating  or  digesting  food.  Those  con- 
nected with  lungs  and  heart  have  to  catch  rest  between 
breaths  and  beats.  The  heart  makes  a  beat  and  a  pause. 
The  pause  is  the  only  rest  it  gets.  During  sleep  it  acts 
slower,  and  has  longer  time  to  rest. 

Diseases  of  Muscle. — Exposure  to  cold  and  wet 
often  causes  muscular  rheumatism,  which  is  an  acute  pain 
in  the  voluntary  muscles.  Generally  a  sharp  twinge  is 
enough  to  make  a  person  careful.  Rheumatism  affects 
various  parts  of  the  body,  but  is  commonest  in  the  neck, 
where  it  is  called  "  wry  neck,"  and  in  the  lower  part  of 
the  back,  where  it  is  called  "  lumbago."  An  attack  of  this 
rheumatism  can  be  prevented  by  wearing  warm  clothing, 
and  by  care  about  exposure  to  weather. 

Getting  wet  is  not  injurious  to  a  healthy  person,  but 
remaining  quiet  in  wet  clothing  and  shoes  is  very  danger- 
ous. Working,  playing,  or  dancing  till  a  person  is  all  in 
a  glow  and  damp  with  perspiration,  then  staying  in  a 


158 


HYGIENE. 


draft,  is  an  almost 
sure  way  to  take  cold. 
Such  a  cold  may  re- 
sult in  acute  pains, 
or  in  some  serious  or 
fatal  illness. 


FIG.  79.  Fatty  Degeneration  of  Heart  Muscle. — 1.  Nucleus;  2.  Fat- 
like  substance. 

The  heart,  as  chief  organ  of  circulation,  is  apt  to  be 
affected  by  diseases  of  other  organs.  Its  muscles  are  sub- 
ject to  several  maladies. 

Enlargement  of  the  Heart  is  an  increase  of  muscu- 
lar tissue  caused  by  disease,  and  also  by  the  use  of  stimu- 
lants and  alcoholic  drinks,  and  by  excess  of  muscular 
action.  It  causes  pain  and  death.  Generally  it  can  be 
prevented  by  temperance. 

Fatty  Degeneration  of  the  Heart  is  an  incurable 
disease.  The  tissue  is  changed  to  a  fatty  substance. 
Muscle  is  contractile;  fat  is  not  contractile;  and  if  the 
latter  tissue  takes  the  place  of  the  former,  it  prevents  the 


HYGIENE  OF  THE  MUSCLES. 


159 


beating  of  the  heart  and  the  circulation  of  blood.  Fig. 
22  shows  healthy  heart  fibres,  and  Fig.  79  shows  fatty 
degeneration.  Imagine  what  would  be  the  consequence 
if  an  order  to  contract  were  to  be  sent  down  a  fibre 
like  that  in  Fig.  79.  It  is  easy  to  understand  that  no 
nerve  impulse  in  the  world  could  keep  a  heart  beating 
that  was  largely  turned  to  fat.  Death  occurs  before  the 
greater  part  of  the  muscle  is  changed.  This  fatty  change 
also  takes  place  in  the  muscular  coats  of  blood  vessels, 
and  destroys  their  elasticity.  Fatty  degeneration  is 
caused  by  many  diseases,  and  frequently  by  the  use  of 
alcoholic  drinks. 

Palpitation  of  the  Heart  is  an  abnormal  quickness 
in  beating.  It  is  apt  to  cause  enlargement.  Excess  of 
muscular,  mental,  and  moral  action,  and  intemperance 
in  stimulants  and  alcoholic  drinks,  are  causes  of  palpita- 
tion, and  may  be  cured,  if  not  too  advanced,  by  temperate 
habits. 


FIG.  80.— Trichina  in  Striped  Muscle. 

Trichina,  or  "Flesh- worm  Disease." — Examine 
Fig.  80  and  notice  what  is  coiled  up  among  the  fibres  of 
muscles.  They  are  small  worms.  They  frequently  get 
into  the  stomachs  of  people  who  eat  raw  or  half  cooked 


160  HYGIENE. 

pork,  and  then  they  burrow  their  way  till  they  reach  the 
muscles.  Here  they  produce  symptoms  something  like 
typhoid  fever.  If  there  are  only  a  few  worms,  the  person 
recovers  after  a  good  deal  of  suffering,  but  if  there  are 
many,  they  cause  death.  The  disease  may  be  prevented 
by  never  eating  pork  unless  it  is  perfectly  cooked,  for 
heat  enough  to  cook  the  pork  kills  the  worms. 


HYGIENE  OF  THE  SKIN.  161 

CHAPTER  4. 

HYGIENE    OF    THE    SKIN. 

Importance  of  a  Healthy  Skin.— The  skin,  one  of 
the  organs  of  excretion,  must  be  kept  in  good  condition. 

The  perspiratory  ducts  constantly  pour  out  perspira- 
tion, the  water  of  which  evaporates,  leaving  the  solid 
parts  on  the  surface. 

The  oil  ducts  give  out  oil,  and  the  dust  in  the  air  sticks 
to  the  oil.  The  waste  material  and  dust  stop  up  the  pores, 
and  prevent  the  escape  of  moisture,  gas,  and  other  waste 
material  that  are  trying  to  work  their-  way  outward. 
This  stoppage  does  great  harm,  for  it  throws  injurious 
substances  back  into  the  circulation,  and  the  lungs  and 
kidneys,  fellow  workers  of  the  skin,  are  overtaxed,  and 
become  diseased,  trying  to  get  rid  of  these  poisons. 

Baths. — The  skin  should  be  kept  soft  and  clean  by 
frequent  baths.  The  question  of  bathing,  like  that  of 
sleep  and  diet,  is  for  each  one  to  decide  for  himself 
according  to  his  need,  but  baths  should  be  taken  as  often 
as  the  system  will  permit  without  inconvenience.  A  test 
of  the  help  or  harm  of  frequent  baths  is  to  notice  their 
effects. 

If  there  is  a  feeling  of  warmth,  comfort,  and  exhilara- 
tion afterward,  a  bath  is  beneficial.  If  there  is  a  feeling 
of  dullness,  heaviness,  and  general  misery,  something  is 
wrong.  There  should  be  a  change  of  hour,  of  tempera- 
ture of  the  water,  or  of  the  room,  or  bathing  should  be  less 
frequent.  Attendant  circumstances,  not  the  bath,  may 
be  to  blame. 

In  California,  where  the  climate  is  so  warm,  a  daily 
morning  bath  is  good  for  any  but  invalids;  but  in  places 
where  the  ice  must  be  broken  on  the  water,  a  sponge  or 


162  HYGIENE. 

plunge  bath  is  too  heroic  treatment  for  ordinary  skins. 
In  places  where  there  is  much  dust,  baths  also  should 
be  frequent. 

Cold  water  is  better  for  bathing  than  warm,  because 
warm  water  opens  the  pores,  and  calls  the  blood  to 
the  surface,  and  there  is  a  danger  'of  chill  afterwards. 
Before  breakfast  is  the  best  time,  for  then  the  body  is 
rested  and  in  good  condition.  The  temperature  of  the 
room  should  be  comfortable,  and  the  body  should  be 
briskly  rubbed  with  a  coarse  towel  so  as  to  cause  a  glow 
over  the  entire  surface. 

People  who  are  sensitive  to  changes  of  climate,  and 
who  chill  easily,  or  who  become  depressed  and  languid 
after  an  ordinary  bath,  generally  find  that  adding  salt  to 
the  water  makes  them  comfortable.  Sea  bathing  has  a 
number  of  things  that  make  it  attractive  as  a  popular  exer- 
cise. The  sea  water  and  air  are  tonic  and  stimulating, 
and  the  surf  and  sunshine  are  added  attractions. 

Persons  with  delicate  skins  have  to  be  careful  about 
using  hard  water,  that  is,  water  containing  too  much 
lime,  and  they  are  also  compelled  to  protect  themselves 
carefully  against  the  action  of  wind  and  sun. 

Chaps. — Chapped  lips  and  hands  are  caused  by  the 
skin  drying  till  it  cracks.  This  is  caused  by  a  hot  or  cold 
dry  wind.  A  preventive  is  to  rub  on  the  skin  a  mixture 
of  four  parts  of  rose  water  and  one  part  of  glycerine,  or 
some  other  oily  compound  that  forms  a  coat  or  protec- 
tion for  the  surface. 

Cosmetics. — The  practice  of  using  paint  and  powder 
for  beautifying  the  complexion  is  one  of  the  dirtiest  and 
most  unwholesome  tricks  of  civilized  women.  A  painted 
face  never  deceives.  The  red  paint  a  greasy  Indian 
streaks  on  his  copper-colored  cheeks,  and  the  rouge  some 
women  put  on  theirs,  are  equally  beautiful  to  the  wearer. 


HYGIENE  OF  THE  SKIN.  163 

If  paint  and  powder  could  be  counted  merely  as  dirt, 
they  might  be  passed  by  as  signs  of  bad  breeding,  or 
attempts  to  cover  up  some  physical  blemish;  but  they  are 
not  so  harmless  as  dirt.  Even  compounds  as  innocent 
as  starch  fill  the  pores  of  the  skin  and  throw  back  waste 
materials  into  the  circulation.  Many  cosmetics,  as  skin 
"  beautifiers  "  are  called,  are  made  from  poisonous  min- 
erals, such  as  arsenic  and  lead.  These  poisons  enter  the 
pores,  pass  to  the  blood  through  the  absorbents,  produc- 
ing serious  and  sometimes  fatal  results.  Many  foolish 
women  have  ruined  ordinary  complexions  by  the  use  of 
powders  and  lotions.  Their  faces  have  become  rough 
and  covered  with  blotches  and  pimples. 

It  is  every  one's  duty  to  look  as  pretty  as  possible,  but 
made  up  faces  are  not  beautiful.  The  best  complexion  is 
made  by  good  respiration,  digestion,  and  circulation, 
which  are  the  results  of  proper  food,  sleep,  and  exercise. 
Nature's  cosmetics  cost  but  little.  If  the  skin  looks 
shiny  or  oily,  as  it  is  apt  to  do  in  warm  weather,  the 
addition  of  a  few  drops  of  ammonia  to  the  bathing  water 
makes  an  improvement.  Ammonia  is  good  to  add  to  the 
water  of  a  full  bath,  as  it  removes  oil  and  makes  the  skin 
fresher  and  sweeter.  If  the  skin  is  dry  and  scaly  the 
rose  water  and  glycerine  lotion  restores  its  softness. 

The  practice  either  of  dyeing,  or  of  oiling,  the  hair  is 
not  so  common  as  formerly.  Hair  dyes  are  injurious  for 
the  same  reasons  that  cosmetics  are.  Bleaching  the  hair 
is  also  injurious.  Besides  destroying  the  gloss  and  soft- 
ness of  the  hair,  the  bleaching  material  is  liable  to  be 
absorbed  by  the  skin. 

Lead  Poisoning. — The  readiness  with  which  the 
pores  of  the  skin  take  up  materials  is  shown  in  many 
cases  of  poisoning.  Painters  who  get  white  lead  from 

paint  on  their  hands  are  often  attacked  with  a  serious 
n-p 


164  HYGIENE. 

illness  called  "painter's  colic."  They  are  also  subject 
to  a  form  of  paralysis,  caused  by  lead  poison.  People 
who  handle  lead  much  in  any  form  are  liable  to  be 
poisoned  through  the  pores  of  the  skin. 

Poison  Oak. — Poison  oak  and  poison  ivy  also  act 
through  the  absorbent  system.  Contact  with  the  growing 
plant  is  generally  necessary  to  poison  a  person,  but  some 
people  are  so  susceptible  that  they  are  poisoned  by  the 
pollen  of  the  blossom  blown  on  them  by  the  wind.  Tar 
soap  has  been  found  to  be  a  simple  remedy  for  the  poi- 
soning by  California  poison  oak. 

Clothing. — Besides  being  kept  clean,  the  skin  should 
be  protected  by  proper  clothing.  Loose,  light  garments, 
thin  in  summer  and  thick  in  winter,  are  best.  Flannel 
should  be  worn  next  the  body  at  all  seasons,  if  possible, 
to  protect  against  sudden  changes.  For  winter  use  flan- 
nel seems  absolutely  necessary.  Clothing  keeps  in  the 
warmth  of  the  body.  The  nap  of  woolen  goods  and  the 
fur  of  animals  tangle  the  air  among  their  fibres,  and  this 
film  of  air  forms  an  extra  coat  for  repelling  the  cold. 

In  California,  where  the  difference  is  great  between  day 
and  night  temperature,  much  care  should  be  taken  in 
regard  to  warm  clothing.  Catarrh  is  prevalent  on  this 
coast,  and  much  of  it  could  be  prevented  by  wearing  flan- 
nel next  to  the  body  all  the  year  around  and  having 
fires  in  the  houses  mornings  and  nights  during  foggy  or 
damp  seasons. 

Since  offensive  waste  material  is  being  constantly  ex- 
haled as  perspiration,  it  is  necessary  frequently  to  change 
clothing,  both  for  health  and  sweetness.  Soiled  garments 
are  offensive  in  every  way.  The  same  clothing  that  is 
worn  during  the  day  should  not  be  worn  at  night.  Fresh, 
loose  garments  should  be  worn  at  night,  and  the  covering 
on  the  bed  should  be  light  and  warm.  Blankets  are 


HYGIENE  OF  THE  SKIN.  165 

better  in  this  respect  than  quilts  and  comforts.  Respi- 
ration and  circulation  being  slower  during  sleep,  night 
air  generally  cooler  than  day  air,  and  the  body  not  able 
to  resist  the  effects  of  exposure  when  the  brain  is  asleep, 
it  is  important  to  have  night  clothing  warm  and  of  the 
best  material  for  protection. 

Colds. — A  change  in  the  weather,  keeping  on  damp  or 
wet  clothing,  riding  in  the  wind,  or  sitting  in  a  draft 
when  warm,  chills  the  surface  of  the  skin,  closes  the 
pores,  checks  the  perspiration,  and  gives  what  is  called  a 
cold.  Care  and  proper  clothing  will  generally  prevent 
colds. 

Taking  cold  depends  very  much  on  the  general  con- 
dition of  the  body  and  mind.  If  a  person  has  been 
overtaxed,  is  addicted  to  alcoholic  drinks  or  other  intem- 
perance, or  is  under  severe  mental  strain,  he  is  less  able 
to  resist  exposure  than  one  who  is  in  good  mental  and 
physical  condition. 

The  intimate  connection  of  the  mucous  membrane  of 
different  parts  of  the  body  is  shown  by  the  effects  of  a 
cold.  A  cold  in  the  head  causes  inflammation  and  swell- 
ing of  the  mucous  membrane  of  the  nose,  and  so  dulls 
the  sense  of  smell.  Articles  of  food  are  tasteless,  mainly 
because  their  odor  cannot  be  perceived.  The  inflam- 
mation extends  to  the  lining  of  the  throat,  and  causes 
sore  throat,  and  may  go  to  the  bronchial  tubes  and 
lungs.  The  tube  that  extends  to  the  throat  from  the  ear 
is  closed,  and  air  cannot  get  into  the  middle  ear,  so  there 
is  dullness  of  hearing.  The  lining  of  the  eyelids  is  also 
affected,  and  the  eyes  become  watery  and  often  blood- 
shot. The  mucous  membrane  that  extends  to  the  air 
cells  of  the  bones  is  swollen,  and  causes  headache. 

As  different  systems  sympathize  with  one  another,  the 
difficulty  may  extend  to  the  stomach,  and  a  slight  cold 


166  HYGIENE. 

is  something  that  ought  to  be  taken  care  of  and  cured, 
to  prevent  serious  results. 

Corns  are  a  hardening  of  the  cuticle,  and  result  from 
wearing  too  loose  or  too  tight  shoes. 

Skin  Diseases. — Skin  diseases,  as  they  are  called, 
are  generally  the  result  of  disorder  of  some  other  system 
than  the  skin.  When  the  skin  is  pimply,  it  is  well  to 
find  out  if  digestion  and  circulation  are  not  at  fault. 

Burns. — Burns  and  blisters,  if  small,  are  easily  cured 
by  keeping  water  on  the  part  burned.  If  a  hand  or  a 
finger  is  burned,  keep  constantly  dipping  it  in  water,  or 
pouring  water  on  it  till  all  pain  leaves.  Then  put  on  a 
bit  of  plaster  to  keep  poisonous  substances  from  reaching 
the  circulation. 

An  extensive  burn  is  more  serious,  and  if  it  covers 
much  surface  is  apt  to  cause  inflammation  of  the  lungs. 
In  this  case,  the  work  of  the  skin  is  thrown  on  the  lungs, 
and  they  become  congested  from  overwork. 


HYGIENE  OF  THE  ALIMENTARY  CANAL.  167 

CHAPTER  5. 

HYGIENE    OF    THE    ALIMENTARY    CANAL. 

Food  is  anything  taken  into  the  body  to  build  up 
tissues  and  keep  up  the  required  heat  of  the  system. 
Generally  it  means  only  the  liquid  and  solid  material 
that  enters  the  alimentary  canal,  but  its  largest  usage 
includes  also  air  taken  into  the  lungs.  In  this  chapter 
only  liquids  and  solids  are  considered. 

Compounds. — In  order  to  know  the  action  of  food  it 
is  necessary  to  know  something  about  its  composition. 
Each  kind  of  food  is  made  of  a  number  of  substances, 
and  is  what  is  called  a  compound.  A  compound  is  some- 
thing composed  of  simpler  materials,  called  elements. 
Wood,  rocks,  and  water,  bone  and  all  the  tissues  of  the 
body,  and  all  food  materials,  are  compounds. 

Elements. — An  element  is  something  that  cannot  be 
divided  into  two  different  substances.  Water  is  a  com- 
pound of  two  elements,  called  oxygen  and  hydrogen, 
and  a  chemist  can  separate  it  into  its  elements,  but  he 
cannot  take  oxygen  or  hydrogen  and  divide  them  into 
two  other  substances.  They  are  already  in  the  simplest 
form  possible.  There  are  altogether  about  sixty-five  ele- 
ments, and  all  the  substances  in  the  world  are  composed 
of  two  or  more  of  these.  About  twenty  elements  are  in 
common  use,  and  the  rest  are  rare.  About  sixteen  are 
found  in  the  body. 

Changes. — When  a  compound  is  decomposed,  as  wood 
and  coal  are  when  burning,  its  elements  are  set  free  and 
they  unite  with  other  elements  to  form  new  compounds. 
Compounds  are  destroyed,  but  elements  are  indestructi- 
ble. Such  changes  are  going  on  all  the  time  inside  as 


168  HYGIENE. 

well  as  outside  of  the  body.  When  we  walk  or  work  or 
think,  parts  of  our  muscles  and  nerves  are  broken  up  by 
the  effort,  and  new  products,  called  waste  material  are 
formed. 

Whenever  a  compound  is  broken  up  and  new  ones  are 
made  from  its  elements,  heat  is  produced.  Heat  is  not 
an  element.  It  is  called  a  force.  The  heat  produced  by 
burning  coal  makes  the  steam  that  drives  an  engine. 
The  heat  made  by  rapidly  burning  wood  warms  our 
houses.  But  when  things  are  broken  up  slowly  the  heat 
is  less,  and  there  is  no  fire.  You  know  how  hard  it  is  to 
get  warmed  by  a  slow-burning  fire.  Blow  it — that  is, 
drive  in  the  oxygen — and  then  there  is  plenty  of  heat. 

Oxidation. — Wood  decomposes  in  the  woods,  produc- 
ing heat,  but  it  takes  so  long  a  time  to  rot  away  that  the 
heat  is  never  felt.  Iron  rusts  in  the  damp  air.  You  can 
scrape  off  the  rust  from  locks  and  hinges,  and  if  they  are 
exposed  a  long  time  they  break  easily;  that  is,  they  are 
burned  up.  When  people  wish  to  keep  iron  work  from 
rusting  they  coat  it  over  with  paint.  It  was  oxygen 
that  made  the  fire  burn  brighter,  and  it  is  oxygen  that 
rusts  or  burns  up  the  iron  slowly;  and  so  ordinary  rust- 
ing, decaying,  or  burning,  is  called  oxidation. 

Something  very  much  like  this  takes  place  in  our 
bodies.  Did  you  ever  think  what  keeps  you  warm?  It 
is  the  oxygen  burning  up  the  tissues  of  the  body,  and  the 
tiny  fires  are  all  over  wherever  blood  carries  oxygen,  and 
food  builds  up  tissue.  If  wood  is  not  added  to  the  fire 
it  soon  burns  out,  and  nothing  is  left  but  ashes.  If  food 
is  not  taken  in  regularly,  the  body  dies.  Suppose  a  per- 
son can  get  no  food.  For  a  little  while  the  small  fires 
go  on  till  all  the  fat  of  the  body  is  used  as  fuel,  then  the 
muscles  waste  till  there  is  little  left  but  skin  and  bone, 
and  the  person  starves  to  death. 


HYGIENE  OF  THE  ALIMENTARY  CANAL.  169 

After  a  person  is  full  grown  he  changes  very  little  in 
weight,  although  every  day  he  eats  several  pounds  of 
food.  The  food  goes  for  fuel,  for  no  matter  how  the 
weather  changes,  the  body  temperature  must  be  kept  at 
about  99°,  or  serious  consequences  result. 

Muscular  Force. — If  a  person  works  hard  he  eats 
more  than  when  he  is  idle.  That  means  that  some  of 
the  food  he  has  eaten  is  changed  to  another  force,  called 
muscular  force.  An  engine  draws  a  train  because  of  heat 
force,  made  by  burning  up  wood  or  coal.  A  horse  draws 
a  wagon,  or  a  man  carries  a  load,  because  of  a  force  called 
muscular  energy,  made  in  his  body  by  burning  up  food. 
This  force  is  sometimes  called  "  work  power." 

The  body  contains  fats,  a  number  of  different  com- 
pounds, like  muscle  and  blood,  and  some  mineral  sub- 
stances, like  lime,  soda,  iron,  sulphur,  and  phosphorus, 
and  in  order  to  keep  working  it  must  get  a  constant 
supply  of  the  same  substances  from  food.  Oxygen  unites 
with  tissues  and  changes  them  to  simpler  compounds. 

Some  of  these  new  compounds  are  exceedingly  harm- 
ful. These  must  be  carried  away,  and  new  compounds 
must  come  immediately  to  supply  the  places  of  worn  out 
tissues,  or  muscles  and  nerves  are  poisoned  and  starved 
and  the  person  becomes  diseased.  This  is  why  we  eat 
and  breathe.  No  food  is  the  same  as  the  part  of  the  body 
it  renews,  but  the  different  foods  must  contain  the  ele- 
ments needed  by  all  parts  of  the  system. 

Vegetables  and  meat  are  taken,  ground  up,  rolled 
around,  dissolved,  and  changed,  and  their  elements  pulled 
apart  and  rearranged  so  that  they  are  no  longer  meat  and 
vegetables  when  they  reach  the  tissues,  but  a  new  mate- 
rial. Each  tissue  picks  out  from  this  substance  in  the 
blood  what  it  needs  and  lets  the  rest  go  on.  A  diet  that 
contains  many  compounds  is  best  for  supplying  all  needs. 


170  HYGIENE. 

Kinds  of  Pood. — Food  can  be  divided  into  two  prin- 
cipal kinds: 

Inorganic. — Water  and  other  minerals. 

Organic. — 1.  Starch;  2.  Fats;  3.  Proteids,  or  Albumin- 
oids. 

Inorganic  Foods. — Inorganic  foods  are  those  which 
are  not  derived  from  any  living  thing;  for  example,  lime, 
salt,  water.  Organic  foods,  as  vegetables  and  meat,  are 
those  that  are  obtained  from  living  things.  The  inor- 
ganic foods  are  generally  taken  in  as  liquids,  or  as  part 
of  organic  material.  Lime,  which  forms  an  important 
part  of  the  bones,  is  taken  partly  in  drinking  water  and 
partly  in  combination  with  various  foods. 

Salt. — Salt  is  added  to  different  foods  in  its  natural 
condition.  It  is  a  necessity.  Even  wild  animals,  like 
deer  and  buffalo,  go  long  distances  to  find  places  where 
salt  springs  have  dried  up,  and  they  lick  the  ground  for 
the  salt.  Such  places  are  called  "  salt  licks." 

When  people  are  deprived  of  salt  they  soon  become 
diseased,  and  the  skin  is  especially  disordered.  (See 
"Scurvy"  in  Glossary.)  Salt  is  taken  as  a  flavoring  to 
many  foods  and  improves  the  taste  of  most  kinds.  The 
elements  that  form  it  are  broken  up,  and  one  of  them 
unites  with  some  other  substances  to  form  gastric  juice. 

Water. — Water  makes  a  part  of  every  tissue,  and 
forms  a  large  portion  of  all  the  liquids  and  solids  taken 
into  the  system,  so  that  a  person  can  live  longer  on  water 
alone  than  on  solid  food  alone.  It  is  given  off  from  the 
body  with  all  excretions,  especially  of  the  kidneys  and 
skin.  A  good  quantity  of  pure  water  used  daily  goes  far 
toward  keeping  a  person  well. 

Pure  Water. — Absolutely  pure  water  is  very  rare  and 
it  is  insipid.  Distilled  water  is  pure.  Rain  water  that 


HYGIENE  OF  THE  ALIMENTARY  CANAL.  171 

has  just  fallen  comes  next  in  purity.  It  is,  however, 
only  pure  in  the  country,  for  in  cities  and  towns  the  rain 
water  in  coming  down  washes  dust,  germs,  and  gases 
from  the  air,  and  is  far  from  pure.  All  water  was  origin- 
ally rain  water.  Ordinary  drinking  waters  contain 
various  minerals,  as  lime,  soda,  sulphur,  or  iron.  They 
get  these  materials  from  the  earth,  through  which  they 
seep,  and  most  people  prefer  water  that  has  some  taste 
of  mineral. 

Impurities  in  Water. — Great  care  should  be  taken 
to  have  drinking  water  free  from  all  impurities.  It  is 
often  polluted  by  the  drainage  of  kitchens,  stables,  or 
sewers.  Limpid  and  clear-looking  water  is  not  always 
pure,  for  organic  matter,  which  is  most  harmful,  is  often 
in  solution,  or  in  such  fine  particles  that  it  cannot  be 
seen ;  while  muddy  water  that  leaves  a  sediment  on  stand- 
ing, though  more  offensive  to  look  at,  is  less  objectionable 
to  drink.  Unless  the  source  of  the  water  is  above  sus- 
picion the  water  should  be  filtered  and  boiled. 

Water  is  the  only  fluid  needed  by  the  tissues.  When- 
ever any  other  liquid  except  milk  or  water  is  used  for  a 
drink,  it  is  either  absolutely  injurious,  as  alcoholic  drinks, 
or  is  a  mixture  of  good  and  bad,  as  tea  and  coffee. 

Organic  Food. — Organic  food  is  divided  into  three 
classes — the  proteids,  the  fats,  and  the  starches.  The 
principal  work  of  proteids  is  to  build  all  the  important 
tissues,  and  of  the  fats  and  starches  to  cause  the  warmth 
of  the  body.  Proteids  are  also  called  albuminoids,  because 
they  all  bear  a  resemblance,  in  use  and  characteristics,  to 
albumen,  the  chief  of  the  tribe. 

Proteids. — The  proteids  all  have  the  following  char- 
acteristics: They  harden,  or  coagulate,  under  certain  cir- 
cumstances, some  on  exposure  to  heat,  some  on  exposure 
to  air,  and  some  on  exposure  to  certain  poisons.  They 


172  HYGIENE. 

contain  a  substance  called  nitrogen;  they  are  complex 
compounds;  they  easily  decompose;  they  are  bad  odored 
when  they  decay;  they  are  all  tissue  builders. 

The  principal  proteids  are  albumen,  fibrin,  gluten,  and 
casein. 

The  common  sources  of  albumen  are  eggs  and  wheat. 
The  white  of  eggs  is  nearly  pure  albumen,  and  this  is  the 
reason  why  eggs  are  such  important  and  nourishing 
articles  of  diet.  They  have  been  called  the  perfect  food, 
because  they  contain  all  classes  of  food — albumen  in  the 
white,  and  fat  and  sugar  in  the  yolk. 

Fibrin  is  found  in  blood  and  the  fibres  of  lean  meat,  and 
the  principal  fibrin  foods  are  beef,  mutton,  pork,  lamb, 
veal,  poultry,  game  birds,  fish,  and  shell  fish.  They  vary 
in  nutritive  qualities  and  digestibility. 

Gluten  is  the  sticky  part  of  wheat  flour.  It  is  also 
found  in  oats,  peas,  and  beans.  It  is  so  much  like  fibrin 
that  it  is  called  vegetable  fibrin. 

Casein  is  the  curd  of  milk;  it  also  forms  a  part  of  peas 
and  beans. 

pats. — Fats  are  taken  into  the  body  as  fat  meat,  but- 
ter, milk,  animal  and  vegetable  oils,  and  oily  nuts  and 
seeds. 

Starches. — The  starch  class  gets  its  name  from  one  of 
its  members,  starch,  which  is  used  in  laundries,  and  from 
corn-starch,  which  is  used  for  making  puddings;  but 
sugars  and  gums  also  belong  to  this  class.  They  are  put 
together  because  they  are  similar  in  action,  and  gum  and 
starch  can  be  changed  into  sugar.  This  change  goes  on 
outside  and  inside  the  body.  Starches  are  generally 
formed  by  plants,  but  some  are  made  by  animals,  as 
sugar  of  milk  and  glycogen.  Starch  is  found  in  most 
grains,  unripe  fruits,  and  in  vegetables.  Sugars  come 
from  sugar  cane,  maple  trees,  beets,  and  some  other 
plants.  Gums  exude  from  many  trees,  as  from  peach  and 


HYGIENE  OF  THE  ALIMENTARY  CANAL.  173 

plum  trees,  but  are  not  of  much  use  as  common  articles  of 
food.  Starch  is  changed  to  sugar  and  sugar  to  fat  by  the 
chemistry  of  the  body. 

Mixed  Diet. — Each  class  of  food  contains  some  of  the 
materials  needed  in  the  body.  No  class  eaten  alone  will 
keep  the  system  in  health.  A  mixed  diet  has  been 
found  to  be  the  most  beneficial.  If  albuminoids,  fats, 
starch  foods,  salt,  and  the  right  drinks  are  used,  it  does 
not  so  much  matter  which  of  the  many  articles  contain- 
ing them  are  eaten  as  how  they  are  cooked  and  how 
they  are  eaten.  In  ordinary  meals  the  classes  of  food 
are  intimately  connected,  as  in  oatmeal  and  milk,  pork 
and  beans,  bread  and  butter,  meat  and  potatoes,  crackers 
and  cheese. 

Good  Bread. — Bread  is  one  of  the  staple  articles  of 
proteid  food.  When  it  is  made  of  coarse  flour,  it  is  more 
nutritious  than  when  made  of  finely  bolted  flour,  because 
much  of  the  best  tissue-making  material  is  sifted  out  of 
the  white  flour.  Graham  or  bran  bread  is  the  best  bread 
of  all.  It  should,  however,  be  home-made  of  sweet  bran 
flour,  for  too  much  of  the  baker's  graham  bread  is  made 
of  a  little  bran  mixed  with  inferior  or  spoiled  flour,  and 
sweetened  to  make  it  pass. 

Oatmeal  and  cracked  wheat  are  deservedly  popular 
foods,  for  they  are  good  tissue  makers. 

The  Best  Meats. — Of  meats,  beef  and  mutton  are  the 
most  nourishing,  and  agree  with  the  greatest  number  of 
people.  Pork  is  generally  harder  to  digest.  Lamb,  veal, 
and  the  meat  of  young  animals  are  more  tender,  but  they 
are  not  so  easily  digested. 

Fish  contains  more  water  than  other  meats.  Shell  fish 
are  rather  to  be  counted  luxuries  than  articles  of  ordi- 
nary diet.  They  are  generally  easy  to  digest.  Cheese  is 
a  nutritive  food  for  people  with  whom  it  agrees,  but  it  is 


174  HYGIENE. 

so  compact  that  it  is  difficult  for  the  digestive  juices  to 
penetrate  it.     It  should  be  well  chewed. 

Beef  Tea. — Beef  tea  is  not  exactly  an  article  of  food; 
that  is,  it  cannot  take  the  place  of  regular  diet  for  any 
length  of  time.  When  made  from  meat  that  is  finely 
chopped  and  left  to  stand  in  cold  water  for  some  time,  it 
forms  a  refreshing  drink,  and  is  good,  in  connection  with 
other  foods,  for  delicate  people  and  invalids.  It  is  a  good 
drink  to  drive  out  chill,  and  to  relieve  a  sense  of  fatigue 
and  faintness. 

Butter. — Butter,  and  fat  of  meat  are  the  usual  forms 
of  fat  food.  Many  people,  whose  taste  rejects  fat  meat, 
do  not  get  enough  fat  material,  because  of  a  popular 
notion  that  butter  must  be  eaten  sparingly.  The  system 
needs  a  great  deal  of  fatty  food,  and  butter  is  one  of  the 
most  palatable  articles  of  its  class.  Let  the  children  put 
the  butter  thick  on  their  bread  if  they  crave  it.  Of 
course,  an  unnatural  appetite  for  this,  as  for  any  food, 
should  be  checked.  Cream  is  a  good  fat  food. 

Olive  Oil. — Oil  of  olives  deserves  to  be  used  much 
more  than  it  is.  When  this  is  made  of  olives  and  is  not 
adulterated,  it  is  sweet  and  palatable;  but,  too  often,  it  is 
mixed  with  other  oils  that  spoil  its  taste,  and  cause  it 
soon  to  become  rancid. 

Vegetable  Diet. — Some  believe  that  the  diet  should 
be  confined  to  vegetables,  and  that  all  the  classes  of  food 
are  found  in  plants.  It  is  true  that  all  classes  of  food 
are  found  in  plants,  but  frequently  they  are  connected 
with  hard  plant  fibre  in  such  a  manner  that  it  takes  a 
larger  bulk  of  material  to  satisfy  hunger,  and  a  much 
longer  time  for  the  food  to  digest.  Meats  contain  a  larger 
amount  of  proteids  and  fats  to  the  pound  than  do  vege- 
tables. They  are  a  concentrated  food,  easily  obtained, 
easily  prepared,  easily  digested,  and  in  common  use. 


HYGIENE  OF  THE  ALIMENTARY  CANAL.  175 

Some  articles  of  diet,  harmless  in  themselves,  become 
injurious  if  taken  together.  For  example,  lobster  and 
milk,  or  cherries  and  milk  have  been  known  to  produce 
dangerous  illness. 

Fruits. — Fruits  are  very  popular  and  very  important 
substances,  that  cannot  readily  be  put  with  ordinary 
classes  of  food.  They  contain  sugar,  water,  and  some 
inorganic  materials,  but  they  are  not  eaten  so  much  for 
these  things  as  for  the  vegetable  acids  and  flavors  they 
contain.  They  are  necessaries  in  warm  climates. 

Spices  and  Condiments. — There  are  a  number  of 
articles  used  with  foods  that  are  not  in  themselves  either 
meat  or  tissue  makers.  They  are  spices  and  flavors,  and 
are  called  condiments;  for  example,  pepper,  mustard, 
horse-radish,  vanilla,  lemon,  and  the  different  herbs 
used  in  dressing  meats,  as  thyme  and  sage.  They  stim- 
ulate the  flow  of  digestive  juices,  and  make  food  taste 
better,  and,  no  doubt,  used  with  moderation,  are  bene- 
ficial. Used  in  excess  they  blunt  the  sense  of  taste,  and 
help  to  cause  dyspepsia. 

Stimulants. — Substances  like  tea,  coffee,  and  alcohol, 
although  differing  greatly  in  results,  are  materials  taken 
not  for  their  food  principles,  but  because  they  nerve  up, 
or  stimulate,  the  system.  They  belong  to  a  class  of  sub- 
stances called  stimulants. 

A  stimulant  is  something  that,  when  taken  in  the 
body,  excites  the  nerves  unnaturally,  and  its  effects  are 
shown  by  various  lively  mental  or  physical  actions. 
Ordinary  objects  stir  the  nerves  in  a  natural  manner; 
as,  for  example,  color  excites  the  optic  nerve,  odors  stir 
the  olfactory  nerve,  and  cold  and  heat  affect  nerves  of  gen- 
eral sensation;  but  stimulants  cause  an  over  excitement, 
and  use  up,  or  waste,  force.  They  act  like  a  spur  on  a 
tired  horse,  and  often  tax  the  system  beyond  endurance. 


176  HYGIENE. 

Tea  and  coffee  are  harmless  stimulants,  if  taken  in 
moderation  by  grown  people.  The  nerves  of  children 
are  so  easily  excited,  and  the  bodies  of  children  are  form- 
ing so  rapidly,  that  they  need  all  their  nerve  impulse  for 
the  purposes  of  nutrition  and  growth,  and  it  is  injurious 
for  children  to  use  tea  or  coffee,  or  any  other  nerve  stim- 
ulant. 

If  the  nerves  are  kept  over  excited  by  foods  and 
drinks,  or  improper  living,  a  person  becomes  what  is 
called  nervous;  that  is,  he  is  irritable  and  ill  tempered, 
and  has,  at  no  time,  proper  self-control.  A  good  deal  of 
the  weakness  and  violent  temper  of  people  is  due  to  the 
use  of  poor  food  and  too  many  stimulants. 

Coffee  and  Tea. — Coffee  and  tea  both  contain  the 
same  stimulating  principle,  which  is  called  caffeine  or 
theine. 

Tea  is  the  dried  leaves  of  the  tea  plant  that  grows  in 
China  and  Japan,  and  great  care  is  taken  in  its  prepara- 
tion. Pure  tea  contains  other  substances  besides  caffeine, 
but  it  is  for  this  principle  that  it  is  used.  Much  of  the 
cheap  tea  is  a  mixture  of  fresh  tea  leaves,  old  leaves  that 
have  been  drawn  for  making  tea,  and  the  dried  leaves  of 
native  plants. 

Coffee  is  the  seed  of  a  plant  that  grows  in  tropical 
countries  in  Asia,  America,  Arabia,  and  Persia.  The 
seed  is  roasted.  Coffee,  as  usually  prepared  with  milk 
and  sugar,  becomes  a  nourishing  drink. 

The  stimulating  principle  of  tea  and  coffee  makes  these 
drinks  restful  and  refreshing  for  many  grown  persons. 
If  they  produce  no  injurious  effects,  such  as  indigestion, 
or  irritability,  or  wakefulness,  they  are  harmless.  They 
are  in  common  daily  use  with  a  great  majority  of  people 
in  civilized  countries.  Each  grown  person  should  judge 
for  himself  whether  he  can  safely  use  them. 


HYGIENE  OF  THE  ALIMENTARY  CANAL.  177 

Soldiers,  after  long  marches,  and  other  men  exposed  to 
extreme  heat  or  cold,  have  proved  that  coffee  is  a  most 
beneficial  drink.  But  used  too  often,  or  too  strong,  tea 
and  coffee  are  causes  of  much  of  the  minor  misery  of  the 
world  in  the  shape  of  bad  temper,  headache,  dyspepsia, 
and  general  irritability. 

Chocolate  and  cocoa  contain  a  small  amount  of  the 
stimulating  principle  of  coffee,  but  they  are  more  nutri- 
tious, because  they  also  contain  some  fats  and  proteids. 

Condition  of  Food.— The  ease  with  which  food  di- 
gests depends  very  much  upon  its  condition  and  prepara- 
tion. All  meats  should  be  so  fresh  that  there  is  about 
them  no  odor  of  decay,  and  all  vegetables  should  be  crisp 
and  unwilted. 

Dried  and  salted,  smoked,  or  pickled  meats  are  not  so 
nutritious  as  fresh,  because  the  salt  and  smoke  have  hard- 
ened their  tissues.  Even  a  great  deal  of  cooking  cannot 
make  them  as  desirable  as  freshly  killed  meat. 

Canned  meats  form  a  good  substitute  for  the  fresh 
article,  if  good  meat  is  put  in  good  cans  and  the  meat  is 
not  allowed  to  stand  in  the  cans  till  it  spoils  after  it  is 
opened.  Cheap  canned  goods  should  be  looked  upon 
with  suspicion. 

Much  discredit  has  been  brought  on  this  useful  kind 
of  food  by  unprincipled  canners,  who  use  spoiled  or  im- 
pure meats,  or  tin  adulterated  with  lead,  or  let  solder  fall 
in  the  cans,  or  cook  the  meat  in  copper  vessels. 

The  acids  of  the  meat  act  on  the  lead  and  copper  of 
the  can  and  kettle  and  on  the  solder,  and  dissolve  enough 
of  these  poisons  off  into  the  food  to  cause  serious  illness 
and  sometimes  death. 

This  is  the  cause  of  some  of  the  cases  of  poisoning 
that  occur  from  eating  tinned  meat.  ,0ne  other  cause  is 
that  people  sometimes  allow  open  cans  of  meat  to  stand 


178  HYGIENE. 

till  the  meat  undergoes  a  first  stage  of  decay,  in  which  it 
acts  as  a  poison.  Canned  foods  should  be  emptied  into 
earthen  or  glass  dishes  as  soon  as  the  cans  are  opened. 

The  strange  thing  about  this  stage  of  decay  is  that  it 
forms  a  most  active  poison,  and  yet  no  change  in  the  meat 
can  be  detected  by  the  senses.  Stewed  chicken*,  and  indeed 
all  kinds  of  meat  are  liable  so  to  change  if  kept  too  long. 

Cooking. — The  object  of  the  various  ways  of  cooking 
is,  besides  tempting  the  appetite,  to  prepare  articles  so 
that  they  remain  as  short  a  time  as  possible  in  the  food 
canal.  An  overworked  stomach,  like  anything  else  over- 
worked, soon  becomes  feeble  and  finds  fault  with  every 
exertion.  Its  grumbling  is  our  pain. 

Cooking  prepares  food  for  the  quick  action  of  the 
digestive  juices.  All  foods,  except  ripe  fruits  and  melons, 
are  improved  by  cooking,  for  this  process  softens  the 
fibres  of  vegetables,  breaks  apart  the  coating  of  starch 
granules,  softens  the  granules  themselves,  softens  fibres 
and  fats  of  meat,  and  loosens  their  connective  tissue. 

Eggs  digest  best  when  soft-boiled,  poached,  or  scrambled. 
If  they  are  boiled  from  five  to  fifteen  minutes  they  are 
very  difficult  to  digest,  but  when  boiled  half  an  hour  or 
more  they  are  easily  digested.  Frying  is  apt  to  fill  their 
pores  with  a  heated  fat  that  is  exceedingly  hard  to  digest. 

Roasting  is  the  best  way  of  preparing  meat.  If  meat 
is  put  in  a  hot  oven,  the  heat  immediately  coagulates  the 
albumen  on  the  outside,  and  this  keeps  all  the  nutriment 
in  and  the  meat  cooks  in  its  own  juices.  Broiling  acts  in 
much  the  same  way. 

Boiling  dissolves  out  the  best  part  of  the  meat  and 
leaves  the  rest  tasteless  fibres.  If  meat  is  boiled,  it 
should  afterward  stand  in  the  liquor  in  which  it  was 
boiled,  in  order  to  absorb  the  juices  that  have  boiled  out. 
Frying  meat  is  objectionable,  for  the  same  reason  that 
frying  eggs  is. 


HYGIENE  OF  THE  ALIMENTARY  CANAL.  179 

Roast  pork  takes  longer  to  digest  than  any  other  meat; 
but  pig's-feet,  boiled  and  eaten  with  vinegar,  digest  the 
quickest  of  ordinary  meats,  and  this  shows  that  the  kind 
of  food  is  not  as  important  as  the  way  in  which  it  is  pre- 
pared. 

Cooking  changes  some  of  the  starch  into  sugar,  and 
softens  simple  starch,  so  that  it  is  easily  acted  on  by 
digestive  juices.  For  this  reason  some  unripe  fruits  that 
would  give  pain  if  eaten  raw,  can  be  comfortably  eaten 
when  cooked. 

There  is  another  forcible  reason  for  having  food  well 
cooked.  Many  insects  lay  their  eggs  on  leaves  of  plants, 
and  most  animals  are  infested  with  parasites.  A  parasite 
is  some  inferior  creature,  like  a  worm,  that  lives  in  the 
food  canal  or  the  muscles  of  a  higher  animal,  and  feeds 
by  absorption  on  the  digested  food  of  the  canal  or  on  the 
lymph  and  plasma  between  the  fibres  of  muscle.  Many 
of  these  degraded  animals  get  into  the  human  system  in 
our  food  and  drink.  Beef,  pork,  mutton,  fish,  and  game 
are  infested  by  various  parasites. 

One  of  the  most  common  parasites  is  the  tapeworm. 
It  is  called  so  because  it  is  flat.  One  kind  comes  from 
pork;  another  from  beef.  They  fasten  themselves  to  the 
walls  of  the  food  canal  and  absorb  the  food  that  would  go 
to  make  tissues,  and  thus  they  cause  sickness,  and  even 
death. 

There  is  another  worm  found  in  pork.  If  uncooked 
pork  that  contains  these  worms  is  eaten,  the  worms  are 
freed  from  the  meat  by  the  digestive  juices  when  the  food 
is  digested,  and  they  bore  their  way  through  the  walls  of 
the  canal  and  bury  themselves  in  the  muscles  (Fig.  80). 

Intestinal  worms,  that  trouble  children,  have  only  one 
way  of  getting  into  the  body,  and  that  is  through  the 
mouth  with  food  and  drink.     Cooking  food  thoroughly, 
and  boiling  water,  will  kill  the  eggs  and  the  parasites. 
12— p 


180  HYGIENE. 

Different  Tastes. — There;  is  a  great  difference  among 
people  as  to  proper  and  improper  articles  of  diet.  Many 
cannot  eat  veal  or  lamb,  fresh  fish,  or  crabs  and  lobsters. 
It  is  not  a  matter  of  taste  .with  them,  but  these  foods 
make  them  sick.  Many  other  kinds  of  food  have  injuri- 
ous effects,  but  are  liked  or  disliked  from  custom  or  indi- 
vidual taste,  such  as  limes,  olives,  fresh  figs,  tomatoes, 
olive  oil. 

Custom  has  much  to  do  with  taste  in  food.  The  peo- 
ple of  Rome  are  said  to  prefer  their  bread  a  little  sour. 
Some  persons  prefer  meat  that  is  tainted;  some  eat  cheese 
from  which  others  turn  with  disgust.  Sour,  spoiled,  and 
foul  odored  food  cannot  be  as  safe  and  nourishing  as 
sweet  and  fresh  material;  but  apart  from  this  the  matter 
of  individual  taste  and  comfort  must  guide  people  in  the 
selection  of  diet. 

Occupation.— Occupation  has  much  to  do  with  the  di- 
gestion of  foods.  A  farmer  or  other  out  of  door  worker  can 
eat  salt  pork  and  potatoes  daily  without  inconvenience, 
because  his  muscular  exercise,  in  the  outside  air,  causes 
his  organs  to  work  well.  The  oxygen  burns  up  the  fat 
and  turns  it  to  energy  or  work.  A  student  or  book- 
keeper or  storekeeper,  shut  up  in  the  house  and  fed  the 
same  diet,  would  be  apt  to  get  dyspepsia. 

Seasons. — Food  should  be  changed  to  suit  the  season. 
In  the  winter,  when  the  outside  air  is  so  cold  that  it  is 
constantly  stealing  away  the  warmth  of  the  body,  more 
fuel  food  must  be  taken.  That  is  the  time  for  fats  and 
starches  and  much  meat.  In  the  summer,  on  the  other 
hand,  one  does  not  need  so  much  warmth.  A  lighter  meat 
diet  and  the  cooling  juices  of  fruits  are  needed. 
,  The  differences  between  the  diet  of  different  nations  is 
a  good  indication  of  the  differences  of  climate.  In  the 
Arctic  regions .  it  is  necessary  to  eat  much  fat.  The 


HYGIENE  OF  THE  ALIMENTARY  CANAL.  181 

Esquimau  must  make  a  little  furnace  of  his  body  for 
burning  up  all  the  blubber  he  can  get  to  keep  from  freez- 
ing to  death.  The  equatorial  man  needs  to  cool  himself 
with  the  juices  of  limes  and  oranges,  and  eats  but  little 
fat. 

The  different  classes  of  food  are  digested  and  absorbed 
in  different  parts  of  the  food  canal. 

Mouth  Digestion. — The  saliva  of  the  mouth,  if  well 
mixed  with  starches,  changes  them  to  sugar,  and  this  is 
absorbed  in  the  stomach.  If  they  are  not  well  mixed 
the  gastric  juice  stops  further  digestion  of  starch  and 
the  food  passes  on  to  the  intestine,  where  it  is  digested 
by  intestinal  juices. 

Stomach  Digestion. — Proteids  are  dissolved  and 
absorbed  in  the  stomach,  if  they  have  been  well  ground 
up,  if  no  other  substance  interferes  with  their  digestion, 
and  if  the  stomach  is  not  overloaded.  If  they  are  not 
digested  in  the  stomach,  they  also  pass  on  to  the  intes- 
tinal juices. 

Intestinal  Digestion. — Fats  are  merely  broken  up 
and  melted  on  the  way  to  the  intestines,  but  not  made 
fine  enough  to  seep  through  the  walls  of  the  alimentary 
canal.  They  are  digested  and  absorbed  in  the  intestines. 
If  more  fat  is  eaten  than  is  needed  for  immediate  heat 
and  motive  force,  it  is  stored  up  as  yellow  masses  among 
the  tissues  of  different  parts  of  the  body.  The  starch 
foods  are  also  changed  to  fat. 

Liver  Digestion. — The  liver  has  the  power  of  con- 
verting all  kinds  of  food  into  an  animal  sugar,  called 
glycogen,  and  this  remains  in  the  liver  till  needed,  or  goes 
among  the  tissues,  and  is  changed  to  fat,  and  is  used  or 
stored  up  according  to  the  requirements  of  the  system. 

Regularity  in  Eating. — Food  should  be  taken  reg- 


182  HYGIENE. 

ularly.  If  the  habit  of  eating  between  meals  is  formed, 
the  stomach  gets  no  time  to  rest.  Its  time  for  rest  and 
re-creating  its  tissue  is  when  no  food  is  being  digested. 
Many  delicate  people  are  not  able  to  eat  enough  at  one 
meal  to  keep  them  till  the  next.  They  should  have  more 
than  three  meals  daily,  but  the  hours  of  eating  should  be 
regular.  Much  depends  on  the  articles  eaten.  A  hearty 
meal  of  vegetables  and  meat  will  last  longer,  and  give 
better  results  in  energy  and  thought,  than  a  light  meal 
of  grains  and  fruits. 

Adulteration. — An  adulteration  is  a  cheap  substance 
added  to  a  good  material,  in  order  that  dishonest  persons 
may  make  more  money.  The  cheap  stuff  costs  much 
less  than  the  good  article,  and  the  mixture  is  sold  for  the 
same  price  as  the  pure  material. 

Nearly  all  articles  of  food,  such  as  milk,  tea,  coffee, 
sugar,  flour,  pepper,  mustard,  are  adulterated.  Some- 
times the  base  material  does  no  great  harm,  as  chicory 
added  to  coffee;  but  in  other  cases  the  cheaper  article  is 
directly  injurious,  as  vinegar  made  from  mineral  acids, 
sugar  or  flour  mixed  with  clay.  The  clay  can  be  detected 
in  sugar,  because  it  cannot  melt.  Powdered  sugar  is 
seldom  pure. 

How  Digestibility  of  Foods  was  Learned. — You 

may  be  curious  to  know  how  foods  were  classified  and 
how  the  different  action  of  the  organs  and  juices  was 
learned.  It  is  partly  a  matter  of  experience,  of  eating 
the  article  and  noticing  its  effect;  but  that  is  a  slow 
and  limited  process.  Many  experiments  have  been 
made  on  dogs  and  other  lower  animals. 

The  most  satisfactory  of  these  experiments  was  made 
on  a  man  who  had  a  gunshot  wound  in  his  stomach.  The 
wound  healed,  and  left  an  opening  about  four  fifths  of 
an  inch  across,  over  which  a  little  flap  of  mucous  mem- 


HYGIENE  OF  THE  ALIMENTARY  CANAL.  183 

brane  hung.  This  little  curtain  could  be  moved  aside, 
and  the  action  of  gastric  juice  on  different  articles 
noticed.  The  condition  of  substances  entering  the  stom- 
ach from  the  gullet,  after  being  acted  upon  by  the  saliva 
alone,  could  also  be  noticed,  and  thus  the  uses  of  both 
the  saliva  and  the  gastric  juice  could  be  determined. 
The  effect  of  irritants  and  unfriendly  substances  was 
also  observed.  The  man  was  a  Canadian,  named  Alexis 
St.  Martin,  and  the  study  of  his  stomach  was  made  by 
Dr.  Beaumont  in  1822. 

Good  health  depends  upon  good  digestion,  and  good 
digestion  depends  on  the  proper  kind,  amount,  and  con- 
dition of  food,  and  the  healthy  action  of  the  food  canal. 
The  great  aim  of  digestion  is  to  get  the  food  dissolved 
and  absorbed  quickly,  and  anything  that  interferes  with 
digestive  action  is  liable  to  cause  disease. 

Bad  teeth,  too  little  of  the  digestive  juices,  or  such 
juices  of  a  poor  quality,  and  inflammation  of  the  mucous 
membrane,  are  the  principal  troubles  of  the  food  canal. 
They  are  caused  generally  by  carelessness,  by  eating  too 
much,  by  improper  and  badly  prepared  food,  by  indi- 
gestible fruits  and  vegetables  in  hot  weather,  rich  and 
highly  spiced  food,  and  by  alcoholic  drinks.  Liver  and 
stomach  troubles  are  to  blame  for  many  of  the  diseases 
of  other  organs. 

A  few  things  need  be  remembered  in  order  to  under- 
stand the  liability  of  the  food  canal  to  injury,  and  the 
reason  other  organs  are  affected  by  its  diseases: 

1 .  The  destination  of  food,  and  the  necessity  of  having 
good  food  and  no  injurious  material. 

2.  The   delicacy   of  the   mucous   membrane,   and   its 
number  of  blood  vessels  and  glands. 

3.  The  microscopic   size  of  glands  and  villi  and  lac- 
teals. 

4.  That  the  liver  is  the  first  place  to  which  the  food 


184  HYGIENE. 

goes  from  the  stomach,  and  the  changes  produced  by  that 
gland. 

5.  The  nature  of  irritation  and  inflammation. 

The  Teeth. — The  teeth  are  the  first  organs  connected 
with  the  preparation  of  food.  They  should  grind  all  foods 
to  the  finest  pulp,  so  as  to  have  the  particles  small  and 
the  saliva  well  mixed  with  them.  If  food  is  eaten  and 
swallowed  slowly  there  is  little  danger  of  overcrowding 
the  stomach,  for  as  it  goes  down  gradually  it  is  dissolved 
and  absorbed,  and  soon  the  appetite  is  satisfied.  Bolting 
food  hurries  down  more  than  the  stomach  needs,  and 
packs  it  in  so  fast  that  the  stomach  is  stupefied  and  can- 
not protest  against  the  amount. 

In  order  to  have  the  teeth  work  well  they  should  be 
clean  and  all  cavities  be  kept  well  filled.  Particles  of 
food  are  apt  to  crowd  between  them  and  cause  decay, 
and  decayed  teeth  make  the  breath  offensive,  and  pro- 
duce much  suffering.  Brushing  the  teeth  with  clean 
water  after  each  meal  is  a  good  habit.  The  use  of  gritty 
tooth  powders  should  be  avoided,  as  they  scratch  the 
enamel. 

Hot  or  very  cold  foods  cause  the  enamel  to  crack,  and 
when  the  enamel  protector  is  injured,  the  softer  dentine 
is  more  readily  destroyed  by  acids  of  the  mouth  and  food. 
Tobacco  makes  the  teeth  yellow,  and  the  breath  offensive. 
Care  of  the  teeth,  and  slowness  in  chewing  and  swallow- 
ing, are  the  first  steps  toward  good  digestion. 

Mucous  Membrane. — The  thinness  of  the  upper 
layer  of  mucous  membrane  allows  the  dissolved  food  to 
pass  through  readily,  but  it  also  allows  injurious  articles 
to  pass  .quickly  through  to  the  delicate  vessels  below, 
and  consequently  mucous  membrane  is  liable  to  get  out 
of  order  if  not  well  treated. 

Pain  is  not  always  the  first  warning  of  a  disordered 


HYGIENE  OF  THE  ALIMENTARY  CANAL. 


185 


mucous  membrane.  As  in  a  cold  the  whole  lining  of  the 
air  passages  is  affected,  so  in  derangements  of  the  lining 
of  the  food  canal  all  parts  may  sympathize;  and  it  often 
follows  that  the  covering  of  the  tongue  is  an  indication 
of  the  condition  of  parts  that  cannot  be  seen,  and  this  is 
the  reason  the  doctor  first  looks  at  a  patient's  tongue. 
A  furred  tongue  is  a  tongue  having  a  thick,  whitish  coat, 
and  this  shows  that  some  part  out  of  sight  is  disordered. 
It  is  often  connected  with  a  bad  taste  in  the  mouth. 


ARTICLES  OF  DIET  TO  AVOID. 


Underdone  meat. 
Stale  meat. 
Stale  canned  meat. 
Cheap  canned  meat. 
Stale  vegetables. 
Kept  over  cold  meats  and  vege- 
tables. 

Unripe  raw  fruits. 
Over  ripe  raw  fruits. 
Very  sour  vinegar. 
Sugar  that  will  not  melt. 
Candy  that  does  not  melt  easily. 


Very  green  pickles. 

Hard-boiled  eggs. 

Boiled  shreddy  meat. 

Half  burned  meat. 

Sour  bread. 

Bread  or  cake  that  tastes  of  soda.' 

Fried  foods.  ' 

All  alcoholic  drinks. 

Lobster  and  milk. 

Cherries  and  milk. 

Anything  that  tastes  musty. 

Hot  bread  or  biscuit. 


HABITS  TO  AVOID. 


Eating  too  fast. 

Talking  of  disagreeable  or  wor- 
rying topics  at  the  table. 

Eating  too  much  or  too  little. 

Eating  wrong  articles. 

Drinking  unboiled  water,  and 
eating  much  fruit  in  cholera 
seasons. 


Tasting  unknown  articles. 

Laughing  violently  while  eat- 
ing. 

Half  chewing  food. 

Drinking  much  while  eating. 

Drinking  very  hot  or  very  cold 
water. 


186  HYGIENE. 


CHAPTER  6. 

ALCOHOL   AND    NARCOTICS. 

General  Effects. — A  stimulant  is  something  taken 
into  the  system  that  excites  unnatural  and  generally 
rapid  action  of  one  or  more  of  its  organs.  A  narcotic  is 
something  that,  in  small  doses,  relieves  pain  and  pro- 
duces sleep;  in  larger  doses  causes  profound  sleep,  or 
lethargy,  and  often  convulsions;  and  in  extreme  doses 
produces  death. 

Stimulants  and  narcotics  are  classed  as  drugs,  and  as 
such  are  useful,  but  none  of  them  should  he  taken  with- 
out the  advice  of  a  skilled  physician. 

Use  and  Danger. — When  organs  become  diseased 
and  cannot  work,  death  is  apt  to  follow  soon  if  something 
is  not  done.  Then  stimulating  drugs  are  used  to  spur 
them  on  or  drive  them  to  work.  Nearly  every  organ 
answers  to  some  spur.  When  the  body  is  diseased,  often 
some  system  is  so  out  of  order  that  there  is  intense  and 
violent  pain.  Then  narcotics  are  useful  to  ease  suffering; 
but  they  are  so  dangerous  in  their  after  effects,  and  the 
habit  of  taking  these  drugs  is  so  easily  ]eamed,  that  they 
should  never  be  used  without  the  order  of  an  experienced 
physician. 

In  ordinary  health  stimulants  and  narcotics  should 
never  be  used,  for  they  stimulate  organs  beyond  their 
strength,  or  stupefy  organs  that  should  be  working.  If 
a  person's  body  or  brain  will  not  work,  it  is  tired  or  sick, 
and  natural  rest  is  what  is  needed. 

Dangerous  Common  Drugs. — Certain  dangerous 
narcotics  and  stimulants  are  so  common,  so  easy  to  ob- 
tain, so  ignorantly  and  recklessly  used,  and  so  deplorably 
fatal  in  their  effects,  that  it  is  every  one's  duty  to  know 


ALCOHOL  AND  NARCOTICS.  187 

about  their  harmful  action.  They  are  of  no  use  to  a 
healthy  body.  Tobacco  and  opium  and  alcohol  are  dan- 
gerous common  drugs.  Opium  and  alcohol  are  drugs  that 
enslave  with  a  terrible  slavery  both  body  and  mind. 

Characteristics  of  Alcohol. — 1.  Alcohol  is  a  color- 
less, spicy,  pungent,  volatile  liquid. 

2.  It  burns  with  a  hot,  colorless  flame. 

3.  It  dissolves  many  things  not  soluble  by  water. 

4.  It  absorbs  water  from  air  and  other  things. 

5.  It  coagulates  albumen. 

6.  It  stimulates  nerves,  and  afterwards  deadens  their 
action. 

It  is  classed  as  a  stimulant  narcotic  poison. 

Uses  of  Alcohol. — Because  its  flame  is  so  hot  and 
does  not  smoke,  alcohol  is  of  use  as  a  burning  fluid.  Its 
solvent  power  makes  it  useful  in  the  preparation  of  med- 
icines and  varnishes.  It  is  used  as  an  antiseptic,  or 
preventer  of  decay,  because  it  coagulates,  or  hardens, 
albumen.  The  white  of  an  egg  placed  in  alcohol  be- 
comes hard  and  white  as  though  cooked.  In  museums, 
specimens  are  put  in  alcohol  and  water,  their  tissues  are 
hardened,  and  they  are  kept  from  decay  for  years. 

The  characteristics  of  alcohol  which  interest  a  student 
of  hygiene  are  its  power  of  depriving  materials  of  the 
water  they  contain,  of  hardening  albumen,  and  of  affect- 
ing nerve  matter. 

How  Alcohol  is  Made. — Alcohol  is  not  found  nat- 
urally in  anything,  but  is  made  from  fruits  and  grains  by 
a  process  called  fermentation.  The  fruits  are  destroyed, 
and  their  elements  form  new  compounds,  one  of  which  is 
alcohol.  If  any  fruit  or  dampened  and  sprouted  grain  is 
crushed  and  kept  in  a  warm  place,  the  sugar  in  it  under- 
goes a  change,  and  before  long  bubbles  of  gas  begin  to 
come  up. 


188  HYGIENE. 

This  happens  when  canned  fruit  is  not  sealed  tightly. 
The  old  substance  is  broken  up,  and  two  .new  ones  are 
made — gas  and  alcohol.  If  left  alone,  the  process  goes  on, 
and  vinegar  is  the  result.  That  is  the  reason  of  the  sour- 
ness of  spoiled  preserves  and  canned  fruit. 

When  alcohol  is  made,  the  fermentation  is  called  alco- 
holic, or  vinous,  fermentation;  when  vinegar  is  made  it 
is  acetic  fermentation.  There  is  a  kind  of  vinous  fer- 
mentation set  up  in  dough  by  yeast  every  time  yeast 
bread  is  made,  and  the  bubbling  gas  trying  to  escape  lifts 
up  the  sticky  dough.  Some  alcohol  is  made,  but  is 
driven  out  of  the  bread  by  heat  when  bread  is  baking, 
for,  you  remember,  alcohol  is  volatile. 

Pure  alcohol  is  never  drank.  Even  alcohol  diluted 
with  water  is  not  a  beverage,  but  there  is  a  great  number 
of  drinks  in  common  use  of  which  alcohol  forms  the  chief 
part  and  the  destructive  principle.  They  are  called  alco- 
holic drinks  or  beverages.  Their  use  has  caused  and  is 
causing  more  evil  and  misery  than  can  ever  be  estimated. 
Their  work  is  a  slow,  progressive  destruction. 

The  proportion  of  alcohol  differs  in  different  drinks. 
Cider  made  from  crushed  apples,  perry  from  crushed  pears, 
wine  from  crushed  grapes  and  small  fruits,  and  beer 
made  from  sprouted  grains,  contain  from  two  to  fifteen 
per  cent  of  alcohol.  The  rest  is  water,  sugar,  and  the 
peculiar  flavor  of  the  fruit  or  of  some  material  put  in  to 
flavor  it.  These  are  called  fermented  and  malt  liquors. 
Other  common  drinks,  which  contain  from  fifty  to  sixty 
per  cent  of  alcohol,  are  called  distilled  liquors.  They 
are  whisky,  brandy,  rum,  and  gin. 

Distillation. — Distillation  is  a  process  of  purifying  a 
liquid  by  heat.  When  chemists  want  water  free  from 
any  mineral  or  organic  impurities,  they  distill  it.  The 
impure  liquid  is  put  in  a  large  boiler,  and  boiled.  From 


ALCOHOL  AND  NARCOTICS.  189 

the  boiler  a  tube  extends  to  another  vessel.  Sometimes 
the  tube  is  coiled  and  sometimes  straight,  and  on  the 
way  between  the  boiler  and  receiver  it  is  kept  cold. 
Sometimes  it  is  coiled  up  in  a  vessel  filled  with  ice.  As 
soon  as  the  liquid  boils  in  the  boiler,  its  steam  goes 
through  the  tube;  here  the  cold  tube  condenses  it,  turn- 
ing it  back  to  a  liquid,  which  drips  slowly  out  of  the  end 
of  the  tube  into  the  receiver. 

Examples  of  condensation  are  seen  on  ice  pitchers  in 
hot  weather,  and  on  kitchen  window  glass  in  cold 
weather,  and  both  cases  mean  that  the  moisture  of  the 
air  coming  in'contact  with  a  cold  surface  becomes  visible 
as  drops  of  water. 

In  making  the  stronger  kind  of  liquors,  different  sub- 
stances, as  fermented  grain  and  potatoes,  or  weaker 
liquors,  as  wine  and  cider,  are  taken  and  distilled,  and 
the  alcohol  quickly  flies  away  from  the  heat,  to  be  con- 
densed with  other  volatile  substances  by  the  cold  pipe. 

Pure  alcohol  is  made  by  frequent  distillations  to  remove 
as  much  water  as  possible.  Gin  and  rum  have  flavors 
added  to  give  them  their  characteristic  taste. 

Adulterations  of  Liquor. — Many  of  the  liquors  in 
daily  use  are  largely  adulterated  with  poisonous  drugs, 
which  add  to  their  deadly  effects.  The  drugs  are  cheaper 
than  the  simple  liquor. 

Large  Doses. — It  is  not  possible  for  a  person  to 
drink  as  large  quantities  of  distilled  liquor  at  a  time  as 
of  water.  Large  drinks  have  been  taken  by  mistake,  or 
on  wagers,  which  have  killed  people  instantly,  or  caused 
death  within  a  few  hours. 

Change. — There  is  a  difference  of  opinion  as  to  the 
change  that  alcohol  undergoes  in  the  body.  So  much 
leaves  the  system  in  an  unchanged  state,  that  it  has, 


190 


HYGIENE. 


given  rise  to  the  opinion  that  none  of  it  is  ever  changed. 
Probably  a  small  portion  is  oxidized,  since  alcohol  has 
a  value  as  medicine,  and  as  it  also  causes  fatty  degen- 
eration, which  is  a  chemical  change  of  tissue. 

Alcohol  Not  Food. — Alcohol  is  not  a  builder  of 
tissue.  It  is  a  compound  in  which  there  is  no  nitrogen. 
Nitrogen  is  an  important  part  of  muscle,  nerve,  and  all 
the  principal  tissues  of  the  body;  therefore,  as  alcohol 
contains  no  nitrogen,  it  cannot  build  nitrogen  com- 
pounds, and  does  not  act  as  a  food.  It  is  to  a  certain 
extent  a  fat  producer,  but  the  fat  may  be  made  at  the 
expense  of,  or  in  place  of,  muscle  or  other  tissue  (page 
158). 

No  Protection  Against  Cold. — Alcohol  will  not 
prevent  chill,  nor  act  as  a  protector  against  cold.  The 
first  flush  of  warmth  that  comes  to  the  surface  of  the 
body  after  drinking  is  caused  by  paralysis  of  the  small 
nerves,  and  the  surface  blood  vessels  distend  with  warm 
blood.  This  gives  a  false  impression  of  the  warming 
power  of  alcohol.  It  merely  deranges  the  circulation. 
The  blood  gives  off  its  heat  to  the  outside  air,  and  goes 
back  to  warmer  parts  chilled,  and  this  causes  the  reaction 
and  chill  that  is  apt  to  follow  the  drinking  of  alcoholic 
liquors. 

Exposure  to  extra  cold  in  winter,  after  the  system  is 
relaxed,  is  apt  to  be  followed  by  serious  consequences. 
It  has  been  the  experience  of  Arctic  explorers  that  men 
cannot  use  alcohol  as  a  protection  against  cold. 

Does  Not  Protect  Against  Heat. — Nor  is  it  a 
protection  against  heat,  for  in  hot  regions  the  drinking 
men  are  the  first  victims  of  the  climate.  Nothing  that 
interferes  with  the  resisting  power  of  the  system  can  be 
beneficial  when  the  body  is  subject  to  much  exposure. 


ALCOHOL  AND  NARCOTICS.  191 

Does  Not  Prevent  Disease. — Nor  can  alcohol  act  so 
as  to  prevent  disease;  but,  on  the  other  hand,  it  causes 
many  diseases  and  gets  the  body  in  condition  for  taking 
many  others.  It  weakens  the  body  and  takes  away  its 
power  of  resistance.  The  system  of  a  healthy  person 
repels,  or  fights  against,  anything  that  disorders  any  func- 
tion of  its  organs,  and  this  is  called  resistance  to  disease. 

Experience,  for  ages,  has  shown  that  this  vigorous 
resistance  of  a  healthy  body  is  destroyed  by  alcohol. 
Intemperate  people  are  first  to  fall  under  exposure  to  cold 
and  heat,  or  when  attacked  by  lung  diseases,  or  when 
cholera  and  smallpox  and  such  diseases  are  common. 

Causes  Special  Diseases. — Not  only  does  it  weaken 
the  system  so  that  a  person  is  more  liable  to  general  dis- 
eases, but  there  are  special  disorders  of  function  and  organ 
that  can  be  traced  to  alcohol.  It  is  a  cause  of  dropsy, 
one  form  of  pneumonia,  two  kinds  of  liver  disease,  and 
a  disease  of  the  kidneys. 

The  two  characteristics  of  alcohol — its  thirst  for  water 
and  its  power  to  harden  albumen — account  for  much  of 
its  dangerous  action;  but  the  reason  of  its  ability  to  in- 
duce fatal  change  in  some  tissues  is  not  understood. 

Degeneration. — The  two  important  changes  produced 
by  this  drug  are  called  fatty  and  fibrous  degeneration. 
In  the  former  a  tissue  loses  its  characteristic,  and  is 
changed  to  a  fatty  substance.  The  cells  of  muscle,  nerve 
matter,  liver,  and  kidney,  may  be  so  altered  that  their 
function  is  destroyed. 

In  fibrous  change  the  connective  tissue  increases, 
hardens,  and  crushes  the  flexible  cells  in  its  meshes  till 
they  get  too  small  to  work.  By  referring  to  pages  200 
and  201  an  idea  can  be  gained  of  the  effect  on  the  body, 
or  on  part  of  it,  of  increasing  the  connective  tissue  at  the 
expense  of  cells. 


192  HYGIENE. 

Injures  the  Stomach. — The  stomach  is  affected  by 
its  use  in  two  ways.  Much  of  the  food  is  albuminoid, 
and  the  digestive  juices  contain  albumen.  Alcohol  hard- 
ens albumen,  and  thus  the  material  that  should  have 
been  dissolved  so  as  to  pass  through  the  walls  of  the 
stomach  and  intestines  stays  undigested  in  the  food  canal 
longer  than  it  should,  and  dyspepsia  ensues.  The  stom- 
ach is  lined  with  mucous  membrane,  This  is  irritated 
and  inflamed  by  alcohol,  and,  if  the  drug  is  much  used, 
causes  ulcerations,  or  hardening  of  the  stomach  walls, 
and  makes  them  too  tough  for  fluids  to  penetrate. 

Injures  the  Liver. — As  the  blood  filters  through  the 
liver  the  alcohol  causes  fibrous  and  fatty  changes  (p. 
199). 

Injures  the  Heart. — The  tissues  of  the  heart  may  be 
altered,  or  its  walls  so  dilated  by  overstrain  that  they 
break. 

Injures  the  Lungs. — The  lungs  may  have  their  air 
cells  hardened,  or  their  capillaries  so  gorged  with  blood 
that  the  liquid  of  the  blood  oozes  out,  and  causes  dropsy. 

Injures  the  Brain. — On  the  brain  the  effect  of  alcohol 
as  a  destroyer  of  tissue  or  function  is  more  terrible  than 
on  other  organs,  for  it  affects  the  will  power,  and  produces 
unconsciousness.  Insanity  is  justly  considered  the  most 
fearful  disease  of  the  human  race,  and  alcohol  produces 
a  temporary  insanity  which  allows  a  man  to  walk  and 
talk,  without  having  the  will  power  to  control  his  mus- 
cles, voice,  or  ideas. 

Different  alcoholic  drinks  have  different  effects,  and 
any  of  them  may  affect  different  individuals  in  different 
ways.  Except  in  cases  of  habitual  drunkards,  all  the 
tissues  of  the  body  may  not  be  affected.  Sometimes  one 
organ  and  sometimes  another  is  diseased  most,  as  is  the 


ALCOHOL  AND  NARCOTICS.  193 

case  when  a  number  of  people  take  cold,  the  cold  affect- 
ing the  lungs  of  one,  the  head  of  another,  and  the  joints 
of  a 'third. 

The  slowness  of  alcohol's  action  in  destroying  tissue, 
the  uncertainty,  till  too  late,  as  to  which  organ  is 
attacked,  and  the  seeming  safety  of  some  persons  till  a 
strain  comes,  keep  unthinking  people  from  appreciating 
its  deadly  effects;  but  if  a  person  has  ever  seen  a  drunken 
man  or  woman,  if  he  has  seen  the  physical  disease  and 
mental  misery  that  come  from  drinking  alcoholic  liquors, 
and  knows  that  drunken  fathers  and  mothers  are  apt  to 
have  idiotic,  imbecile,  and  diseased  children,  he  knows 
that  alcohol  is  a  dangerous,  poisonous  drug,  that  is  abso- 
lutely injurious  to  a  healthy  body. 

ALCOHOL. 

CHARACTERISTICS.  CAUSING 

1.  Affinity  for  water Corpuscles,    capillaries,    liver 

cells,   air  cells,  and  muscle 
cells  to  shrink. 

2.  Coagulates  albumen Plasma,  digestive  juices,  food, 

and  muscles  to  harden. 

3.  Degenerates  tissue Liver,    heart,     blood    vessels, 

kidney,  and  brain  to  change 
tissue. 

4.  Deadens  function  of  nerve  matter.  .  Loss  of  muscular  control  and 

loss  of  will  and  mental  fac- 
ulties. 

NARCOTICS. 

Opium. — Opium  is  one  of  the  commonest  of  narcotics. 
It  is  made  from  the  juice  of  a  poppy,  cultivated  in  India 
and  China.  From  this  juice  a  number  of  differently 
named  substances  are  made,  as  morphine,  laudanum, 
paregoric,  and  soothing  syrups. 

Opium  that  is  used  for  smoking  is  a  brownish,  sticky 
gum.  It  is  put  in  a  peculiar  kind  of  pipe  and  smoked, 
.  and  the  smoke  has  the  stimulating  and  the  narcotic  effect. 


194  HYGIENE. 

It  is  used  a  great  deal  in  this  way  by  the  Chinese  and 
eastern  nations,  who  do  not  use  alcoholic  beverages. 

Opium  produces  a  kind  of  intoxication  that  is  as 
destructive  to  its  victim  as  that  of  alcohol,  but  does  not 
lead  to  similar  acts  of  violence  to  others  and  the  destruc- 
tion of  property,  that  alcoholic  intoxication  is  apt  to 
produce.  A  small  quantity  causes  stupor,  which  ends  in 
death  to  one  who  is  not  used  to  it;  but  the  opium  smoker 
from  habit  can  take  a  dose  that  would  kill  a  person  un- 
used to  the  drug,  though  he  finally  reaches  a  point  where 
it  is  death  to  stop  and  death  to  continue. 

When  the  habit  becomes  fixed,  an  attempt  to  break  it 
produces  such  painful  effects  on  the  system,  that  it  is 
next  to  impossible  for  an  opium  slave  to  free  himself. 
And  the  consequences  are  as  bad  if  he  keeps  on,  for  the 
drug  finally  kills. 

Used  frequently,  it  disorders  the  different  organs, 
causing  dyspepsia,  an  irregularity  of  secretion  and  of 
the  nervous  system,  and  an  aversion  to  mental  and 
physical  work.  It  blunts  the  moral  sense,  and  weakens 
the  will,  till  it  is  said  of  opium  takers  that  they  are 
generally  untruthful  and  dishonest.  Finally,  the  nerv- 
ous system,  so  overtaxed,  is  unable  to  work,  and  the 
digestive  organs  fail  to  act,  and  the  victim  dies  of  starva- 
tion. There  is  very  little  danger  of  a  person  becoming 
an  opium  slave  through  smoking  unless  he  so  wills,  but 
there  is  great  danger  of  unconsciously  falling  a  victim  to 
the  other  forms  of  this  drug,  and  against  which  all  should 
be  warned. 

The  substances,  morphine  and  laudanum,  made  from 
opium,  affect  the  body  much  as  opium  does;  they  are 
given  as  painkillers  by  physicians,  and  sometimes  the 
patient,  without  fully  understanding  his  danger,  admin- 
isters a  dose  to  himself  for  some  slight  pain  or  for  wake- 
fulness.  He  repeats  it  as  he  thinks  he  needs  it,  until, 


ALCOHOL  AND  NARCOTICS.  195 

before  he  realizes,  he  has  formed  the  habit,  which  takes 
more  than  usual  strength  of  will  to  break. 

In  the  first  place,  every  one  should  school  himself  to 
endure  slight  pain,  and  so  develop  strength;  and  in  the 
second,  no  painkiller  or  soother  should  be  given  with- 
out a  doctor's  order.  Paregoric,  which  is  a  sweetened  and 
diluted  laudanum,  is  often  given  to  babies  to  make  them 
sleep.  This  is  a  dangerous  practice,  for,  besides  deranging 
the  child's  system,  the  drug  may  develop  in  his  brain 
a  desire  for  narcotics,  or  a  toleration  of  them,  that  may 
wreck  his  life.  Soothing  syrups  are  generally  prepara- 
tions of  opium,  and  they  should  never  be  used.  A  child 
that  is  well  sleeps  as  much  as  it  needs  to,  and  a  sick  child 
should  not  be  drugged  to  insensibility. 

Bitters. — Bitters  and  quack  medicines  are  prepara- 
tions in  which  some  cheap  material  is  generally  mixed 
with  alcohol,  and  the  habit  of  using  them  is  frequently 
only  an  excuse  for  taking  alcoholic  liquors.  The  folly 
of  doctoring  one's  self  with  unknown  medicine,  for  an 
unknown  disease,  is  obvious  enough  to  any  one  but  the 
taker  of  patent  medicines. 

Tobacco. — Doctors  have  about  given  up  the  use  of 
tobacco  as  a  drug,  because  of  its  dangerous  and  uncertain 
effects,  but  the  mass  of  people  ignorantly  regard  it  as 
harmless.  It  contains  a  poison  called  nicotine.  It  is 
an  exciter  of  the  nerves,  and  so  induces  heart  disease 
by  forcing  the  heart  to  over  exertion.  It  irritates  the 
mucous  membrane,  and  thus  produces  diseases  of  the 
nose,  throat,  lungs,  and  stomach. 

It  dulls  the  hearing  and  eyesight.  But  its  greatest 
evil  to  growing  people  is  that  it  stunts  growth  by  stimu- 
lating the  glands  to  excessive  secretion.  The  glands 
form  their  secretions  from  the  albuminoids  in  the  blood, 
and  if  these  materials  are  used  up  by  the  glands,  for  no 


196  HYGIENE. 

useful  purpose,  the  tissues,  which  are  made  of  the  same 
materials,  suffer  and  are  unable  to  develop. 

In  this  way  a  growing  boy  robs  his  body  and  does  not 
grow  to  be  a  full  sized,  well  developed  man.  No  matter 
what  may  be  said  for  or  against  the  use  of  tobacco  for 
men,  there  is  no  doubt  that  this  drug  stunts  the  bodies 
and  dulls  the  mental  faculties  of  young  boys,  and  should 
never  be  used.  One  of  the  most  dangerous  forms  of 
tobacco  is  the  cigarette.  Its  use  among  boys  is  so  com- 
mon and  so  pernicious  that  laws  have  been  made  against 
the  sale  to  minors  of  tobacco  in  this  form. 

Cigarettes  are  worse  in  many  ways  than  other  forms  of 
tobacco.  They  are  made  of  stumps  of  cigars  picked  up 
in  the  street,  that  may  come  from  diseased  mouths,  and 
of  cheap  refuse  of  other  cigars.  The  smoke  of  the  paper 
is  added  to  the  tobacco  smoke  and  is  drawn  quickly  into 
the  lungs.  The  porousness  of  the  cigarette  allows  the 
heat  as  well  as  smoke  to  enter  the  mouth. 

Cases  of  death  have  been  known  to  occur  from  excess- 
ive cigarette  smoking.  The  commonest  result,  however, 
is  a  breaking  down  of  health  and  a  weakening  of  the 
mind,  which  leaves  the  cigarette  slave  a  miserable  wreck, 
to  keep  on  living  long,  wretched  years  when  life  is  a 
burden. 

POISONS  AND  ANTIDOTES. 

A  poison  is  something  that  injures  or  destroys  the  tis- 
sues if  taken  into  the  system.  An  antidote  is  something 
taken  to  prevent  the  action  of  poison.  A  number  of 
common  poisons  that  are  used  for  killing  rats  or  gophers, 
or  for  poisoning  flies,  may  poison  children,  if  carelessly 
left  within  their  reach.  Poisons  should  always  be  plainly 
marked,  and  hidden  away. 

Milk  and  the  white  of  raw  egg  are  substances  that  it  is 
safe  and  beneficial  to  give  in  nearly  all  cases  of  poisoning. 


POISONS. 


197 


Many  poisons  harden  albumens,  and  when  a  hard  mass 
is  made  around  a  poison  it  cannot  destroy  tissue.  Soon 
after  the  egg  (which  is  the  best  common  antidote)  is 
taken,  give  an  emetic  to  remove  the  poison  from  the 
system,  for  if  it  is  left  the  gastric  juice  will  dissolve  the 
egg  and  liberate  the  poison. 


SOME  COMMON  POISONS,  AND  HOW  TO  TREAT  CASES  OF  POISONING. 


Remedies. 


Poisons. 


Antidotes. 


Give  an  emetic 

(Mustard  and  water.  Hot 
water.  Tickle  throat  with 
finger  or  feather  to  pro- 
duce vomiting.) 


Morphine  .  .  . 

Laudanum  

Strong  Coffee. 

Stramonium  
Water  Hemlock.  .  .  . 
Tobacco 

Keep  the  person 
awake  by  any 
means. 

Strychnine.  . 

Arsenic  (Rat's-bane).  }•  Magnesia. 
Flypaper  poison. 
Paris  Green. 

Sugar  of  Lead }•  Epsom  Salts. 

White  Lead. 


Never  use  an  emetic,  for 
these  are  burning  sub- 
stances, and  would  burn 
coming  up  as  well  as  going 
down. 


f  Ammonia }•  Cooking  Soda. 

Lunar    Caustic     (Ni- 

trate  of  Silver).  .  .  J-  Common  Salt. 
Corrosive    Sublimate 
(Bug  Poison)  ........  J-  White  of 

and  Milk. 
Oxalic  Acid  (Salts  of  1 

Lemon) [  Chalk' 

Any  strong  acid.  .  .  .  j  Magnesia. 
[  Blue  Vitriol }.  Eggs. 


Sting  of  insects . 


.  }•  Ammonia.    Com- 
mon Soda. 


Snake  bites  .  ;  .  J-  Whisky  or  Brandy  in 
small  doses,  a  pint 
or  more. 


198  HYGIENE. 

DISEASES  TO  AVOID. 

Dyspepsia:  A  disease  of  the  stomach  caused  by  want  of 
quantity  or  quality  of  gastric  juice;  it  affects  digestion. 
Hasty  and  irregular  eating,  worry,  and  too  much  food 
are  causes. 

Drunkard's  dyspepsia:  A  congestion  of  the  vessels  of 
mucous  membrane,  enlargement  and  change  of  the 
tissue  of  the  glands,  affecting  stomach  digestion. 
Cause,  alcoholic  drinks. 

Gastric  irritation:  An  inflammation  of  the  mucous  mem- 
brane, causing  imperfect  digestion  and  fever.  Caused 
by  too  hot  or  too  cold  liquids,  errors  of  diet,  and  alco- 
holic drinks. 

Gastric  dilation:  Increase  of  the  cavity  of  the  stomach, 
with  changes  in  the  tissues  of  its  walls.  The  cause  is 
sometimes  cancer,  often  excessive  beer  drinking. 

Intestinal  dyspepsia:  A  disease  resulting  from  decompo- 
sition of  chyme;  its  causes  are  over  eating,  worry,  want 
of  exercise,  improper  food,  and  immoderate  use  of 
tobacco. 

Diarrhoea:  A  derangement  of  the  intestines  that  occa- 
sions weakness  and  pain;  caused  by  over  eating,  and 
by  impure  water  and  food.  Acute  diarrhoea  comes 
from  eating  improper  and  indigestible  food,  and  from 
exposure  to  hot  and  changeable  weather. 

Cholera  morbus:  An  acute  pain,  caused  by  irritation  of 
the  mucous  membrane  of  intestines,  brought  on  by  irri- 
tating drugs,  hot  weather,  and  eating  unripe  fruit  or 
vegetables. 

Cholera  infantum:  An  inflammation  of  mucous  mem- 
brane of  the  stomach  and  intestines,  produced  by  im- 
proper food,  impure  air,  and  uncleanly  surroundings. 


DISEASES  TO  AVOID. 


199 


Dysentery:  Diseased  condition  of  the  mucous  membrane, 
brought  about  by  inattention  to  proper  habits  of  eat- 
ing, to  an  insufficient  supply  of  pure  air,  and  by  lack 
of  cleanliness  of  person  and  surroundings. 

Jaundice:  A  disease  of  the  bile  ducts,  caused  by  malaria 
and  by  over  eating. 

Biliousness :  An  enlargement  of  the  liver,  and  an  excessive 
fullness  of  its  vessels,  caused  by  malaria,  excess  in 
eating  and  drinking,  and  by  alcoholic  drinks. 

Fatty  degeneration  of  the  liver  is  a  change  of  normal 
liver  cells  into  fat  material,  and  one  of  the  principal 
causes  is  the  use  of  alcoholics.  The  liver,  as  the 


T.  II. 

FIG.  81. — I.  Three  Lobules  of  Normal  Liver. 
II.  Fatty  Degeneration  of  Liver. 

largest  gland  of  digestion,  receives  a  great  deal  of 
the  blood  from  the  food  canal.  It  has  a  great  deal  to 
do.  All  goes  well  with  the  liver  when  the  lobules 
are  like  Fig.  81,  I.,  and  under  the  microscope  the 


200 


HYGIENE. 


zigzag  capillaries  produce  a  pretty   effect;   but  if  fat 
comes  (Fig.  81,  I.  1),  all  trace  of  capillaries  and  liver 


FIG.  82.  Hob-nailed  Liver.— 1.  Intralobular  Vein ;  2,  2.  Connective 
Tissue;  8.  Lobule. 


FIG.  83.  Section  of  Abnormal  Liver.— 1.  Fat  Cells  in  place  of  Hepatic 
Cells ;  2.  Connective  Tissue  much  increased. 


DISEASES  TO  AVOID.  201 

cells  disappears.     There  is  a  loss  of  structure  that,  if  it 
extends  to  many  lobules,  means  death. 

In  Fig.  82  there  is  another  change  shown.  The  cells  are 
crowded  in  little  patches,  and  the  wide  path  of  con- 
nective tissue  shows  the  cause.  This  is  a  case  of  fibrous 
change. 

In  Fig.  83,  it  is  not  difficult  to  recognize  the  material. 
Compare  it  with  Fig.  81,  I.  Compare  Figs.  81,  82,  83, 
in  regard  to  connective  tissue,  fat,  and  liver  cells. 
These  are  not  fancy  pictures,  but  drawn  for  this  book 
from  pieces  of  human  liver,  put  under  the  microscope, 
to  show  how  alcohol  affects  this  organ. 

Hob-nailed  liver,  or  gin  drinker's  liver:  A  disease  where 
connective  tissue  increases  and  crowds  the  liver  cells 
till  they  shrink  and  harden,  and  the  whole  organ  be- 
comes contracted  in  bunches.  Caused  by  use  of  alco- 
holic drinks  (Fig.  82). 


202  HYGIENE. 

CHAPTER  7. 

HYGIENE    OF    THE    ORGANS    OF   CIRCULATION. 

Secondary  Diseases. — The  organs  of  circulation  are 
generally  affected  more  in  a  secondary  manner,  that  is, 
by  the  diseases  of  other  organs,  than  by  a  primary  dis- 
order of  their  own  function.  This  is  especially  true  of 
the  blood.  If  anything  interferes  with  the  action  of  the 
glands  of  the  food  canal,  or  of  the  organs  of  respiration, 
these  organs  are  not  able  to  act  normally  on  the  blood 
that  comes  to  them,  and  it  is  easy  to  perceive  how,  in 
this  case,  a  different  and  harmful  fluid  comes  through 
the  blood  vessels.  This  is  an  illustration  of  the  depend- 
ence of  organs  on  one  another.  The  way  to  prevent  bad 
blood  is  to  remove  the  cause  that  is  destroying  the  func- 
tion of  the  organs  that  prepare  and  purify  blood.  The 
heart,  as  a  muscular  organ,  is  liable  to  diseases  of  mus- 
cle (p.  158),  but  its  other  tissues,  the  valves  and  the  heart 
cover,  are  sometimes  disordered. 

Diseases  of  Valves. — The  valves  shut  up  in  order 
to  give  the  blood  a  constant  single  direction.  All  the 
valves  are  liable  to  diseases  which  shrink  them  so  they 
cannot  shut  tightly,  or  thicken  them  so  they  cannot  fully 
open,  and  consequently  some  of  the  blood  flows  back 
against  the  current. 

Imagine  the  disease  (which  is  one  of  the  most  com- 
mon) of  the  valve  between  the  left  auricle  and  left  ven- 
tricle. The  contraction  of  the  auricle  drives  the  blood 
into  the  ventricle;  then  the  ventricle  contracts  and, 
instead  of  the  valve  shutting  tightly,  and  thus  causing 
all  the  blood  to  go  to  the  aorta,  it  only  partly  closes  and 
some  of  the  blood  is  forced  back  into  the  auricle.  But 
enough  blood  to  fill  the  auricle  has  just  come  down  from 


HYGIENE  OF  THE  ORGANS  OF  CIRCULATION.          203 

the  lungs,  and  the  two  crimson  tides  meet.  Some  is 
pressed  back  to  the  lungs  and  acts  as  an  obstruction,  and 
some  presses  on  to  the  disabled  valve,  and  again,  by  the 
same  process,  a  return  current  starts  for  the  lungs.  So 
it  keeps  on  with  every  beat  of  the  heart,  till  the  lung 
capillaries  are  distended,  then  the  liquid  of  the  blood 
oozes  through  their  thin  walls  into  the  lung  tissue  and 
inside  the  pleura. 

This  constant  flowing  backward  also  interferes  with 
the  right  auricle  and  ventricle,  for  it  causes  them  to  get 
overfull  so  that  their  walls  dilate  and  thus  become  thin. 
The  venous  blood  from  the  system,  always  having  its 
quantity  increased  by  the  products  of  digestion,  also  gets 
a  set-back  and  crowds  into  the  capillaries.  Here  again 
the  liquid  of  the  blood  oozes  through  the  thin  walls. 
This  obstruction  of  circulation,  whatever  valve  may  be 
the  cause,  if  long  continued  produces  the  disease  called 
dropsy. 

Dropsy  is  an  unnatural  accumulation  of  liquid  from 
the  blood  in  the  cavities  or  tissues  of  the  body.  The 
injury  to  valves  is  caused  by  excessive  overwork,  or  heart 
strain,  a  forcing  of  the  valves  to  open  and  shut  oftener 
than  they  are  able. 

Inflammation  of  the  heart  sac  and  the  accumulation 
of  water  in  the  heart  sac  are  secondary  diseases.  Often 
they  are  a  result  of  Bright's  disease  of  the  kidneys,  and 
this  disease  is  caused  by  excess  in  eating  and  drinking 
and  by  the  use  of  alcoholic  liquors. 

Suppose  any  one  were  foolish  enough  to  put  water  in 
his  watch,  or  sprinkle  dust  on  the  small  wheels,  what 
would  be  the  consequence?  Suppose  the  watch  were 
alive  and  could  feel  the  pain  of  these  foreign  substances, 
and  that  the  life  of  a  human  being  depended  on  its  keep- 
ing on  running,  and  you  have  a  pretty  good  idea  of  the 


204  HYGIENE. 

consequence  of  disorders  of  the  valves  and  the  cover  of 
the  heart. 

Faintness. — Sometimes  a  person  becomes  pale,  loses 
consciousness,  and  falls  down  in  what  is  called  a  faint. 
It  means  that  the  brain  has  not  enough  blood.  Some- 
thing like  want  of  food,  a  fright,  or  other  great  nervous 
excitement  interferes  with  circulation,  and  this  stops  the 
function  of  the  brain.  The  person  should  be  placed  with 
.  his  head  lower  than  his  feet;  in  extreme  cases,  a  pillow 
or  cushion  can  be  put  under  the  legs,  so  that  the  blood 
can  go  back  to  the  head  readily. 

Bleeding. — A  knowledge  of  the  different  ways  in 
wThich  blood  flows  from  veins  or  arteries  is  of  great  service 
when  a  blood  vessel  is  cut.  There  is  not  much  harm  in 
small  wounds,  but  when  large  vessels  are  cut  there  is 
danger  of  the  blood  flowing  out  so  freely  as  to  cause 
death.  Blood  goes  from  arteries  in  jerks,  or  spurts;  and 
from  veins,  in  a  steady  flow. 

Cold  water,  or  cold  articles,  placed  near,  but  not  on  the 
wound  (for  fear  of  removing  the  forming  clot),  chill  the 
vessels  of  the  surface,  so  that  they  contract  and  send  the 
blood  to  other  parts  of  the  body.  Pressure  causes  the 
blood  to  move  slower,  and  to  give  that  which  is  exposed 
to  the  air  a  chance  to  coagulate.  Almost  all  an  ordinary 
person  can  do  is  to  apply  something  cold,  and  press  the 
wound,  and  put  on  soft  cloths  to  absorb  the  blood  and 
help  in  coagulation.  If  these  do  no  good,  and  the  wound 
is  on  one  of  the  extremities,  tie  a  cloth  tightly  near  the 
wounded  part,  between  the  wound  and  the  heart,  if  an 
artery  is  cut,  for  the  arterial  current  is  flowing  toward 
the  wound;  or  on  the  side  away  from  the  heart,  if  a  vein 
is  cut. 

In  ordinary  nose  bleed  press  hard  against  the  side  of 
the  nose  where  the  bleeding  occurs,  till  a  clot  is  formed. 


HYGIENE  OF  THE  ORGANS  OF  CIRCULATION.         205 

Wounds. — Wounds,  especially  those  on  the  hands,  no 
matter  how  small,  should  be  well  covered  with  plaster. 
This  keeps  the  many  injurious  substances  that  come  in 
contact  with  the  surface  from  entering  the  circulation  by 
way  of  the  absorbent  vessels.  Always  keep  a  cut  well 
covered. 

Cutting  corns  till  they  bleed  is  dangerous,  because 
some  material  from  the  knife,  or  from  the  stockings,  may 
enter  the  blood,  and  cause  what  is  called  blood  poisoning. 

Regulation  of  Blood  Supply.— There  is  not  enough 
blood  in  the  body  to  keep  all  the  tissues  and  organs  work- 
ing their  best  at  the  same  time,  so  when  one  set  of  organs 
works  another  rests.  This  means  that  the  blood  vessels 
are  more  expanded  and  the  flow  of  blood  faster  in  the 
exercised  part,  and  the  blood  vessels  contracted  and  the 
flow  of  blood  slower  in  the  resting  part.  The  resting 
tissues  get  only  enough  blood  to  keep  them  healthy, 
while  the  exercised  tissues  get  much  more.  The  regula- 
tion of  amount  of  blood  is  done  by  the  muscular  walls 
of  the  smaller  blood  vessels  under  the  influence  of  nerves. 
Such  changes  in  amount  of  blood  take  place  constantly. 
The  alimentary  canal  calls  for  extra  blood  during  diges- 
tion; the  muscles  during  exercise;  the  brain  during 
study;  and  as  the  supply  is  not  enough  for  all  to  have, 
at  the  same  time,  the  amount  needed  for  hard  work,  any 
attempt  to  carry  on  the  active  work  of  many  organs  at 
once  causes  serious  disturbance  of  function.  Conse- 
quently, one  cannot  study  well  after  a  full  meal,  for  the 
digestive  organs  need  the  blood,  and  the  brain  also  needs 
it.  Violent  exercise  after  a  full  meal  acts  the  same. 
When  the  brain  is  overworked  and  the  face  flushed, 
weariness  and  headache  may  be  prevented  by  some  exer- 
cise that  calls  the  blood  to  the  muscular  system.  When 
a  person  is  chilled  by  exposure,  that  is,  the  blood  has 


206  HYGIENE. 

been  driven  by  cold  from  the  surface,  one  may  avert  seri- 
ous consequences  by  rapid  exercise,  or  a  brisk  rubbing  of 
the  body  with  coarse  towels,  till  the  surface  is  aglow. 

Cold  Feet  and  Hands. — Many  people  suffer  a  great 
deal  from  cold  feet.  The  cause  may  be  imperfect  circula- 
tion or  poor  blood.  Hands  and  feet  ought  never  to  be 
habitually  cold.  Their  coldness  is  a  reflection  on  the 
good  sense  of  their  owner,  if  he  is  in  ordinary  health,  for 
it  means  bad  habits  of  some  kind. 

If  change  of  habit,  such  as  sleeping  more,  taking  more 
fresh  air  exercise,  changing  diet,  or  removing  tightly  laced 
clothing  and  tight  shoes,  so  as  to  allow  the  general  circu- 
lation to  remedy  and  cure  the  inconvenience,  does  not 
answer,  there  is  something  the  matter  that  needs  the 
attention  of  a  physician. 

Congestion. — Congestion  is  the  unnatural  accumula- 
tion of  blood  in  any  part  of  the  body,  and  is  caused  by 
an  obstruction,  or  by  something  that  calls  the  blood 
faster  than  it  can  get  away.  It  is  usually  accompanied 
by  swelling,  because  the  tissues  get  overfull;  redness  or 
inflammation,  and  heat,  because  of  the  quantity  of  blood; 
and  pain,  because  the  nerves  are  crowded.  A  mosquito 
bite  is  a  local  congestion,  caused  by  the  poison  of  the 
insect. 

Kidneys. — The  kidneys,  as  organs  for  excreting  much 
of  the  waste  matter,  are  liable  to  many  diseases.  These 
diseases  come  from  overloading  the  system  with  more 
good  material  than  can  be  worked  up,  or  taking  in  stim- 
ulants and  irritants,  and  highly  spiced  foods,  that  the 
body  has  no  need  of,  or  from  exposure  to  cold  and  damp, 
and  all  these  acts  throw  more  work  on  these  organs  than 
they  can  do.  Alcohol  probably  causes  more  kidney  dis- 
eases than  all  other  things  put  together,  because  it  has 


HYGIENE  OF  THE  ORGANS  OF  CIRCULATION. 


207 


no  use  to  serve,  there  is  no  demand  for  it  in  a  healthy 
body,  and  it  must  be  exhaled.  There  is  one  form  of 
disease,  called  Bright's  disease  of  the  kidneys,  which 
frequently  has  alcohol  for  a  cause,  and  it  induces  disorders 
of  many  other  organs.  In  fact,  if  the  kidneys  do  not 
cast  out  the  waste  matter,  it  goes  through  the  whole 
body,  poisoning  its  tissues. 


THINGS  TO  AVOID. 


Over  work. 

Over  excitement. 

Violent  temper. 

Anything  that  violently  in- 
creases heart  action. 

Developing  one  part  of  the 
body,  as  the  muscles,  at  the 
expense  of  another. 

Bad  air. 

Bathing  soon  after  hearty 
meals. 


Exposure  to  damp  and  cold. 

Use  of  stimulants  and  nar- 
cotics. 

Too  few  hours  of  rest. 

Skinning  or  handling  animals 
that  have  died  of  disease. 

Bathing  after  violent  exercise. 

Sudden  checking  of  perspira- 
tion, as  sitting  in  a  draft,  or 
putting  cold  water  on  face 
and  head  when  over  heated. 


208  HYGIENE. 

CHAPTER   8. 

CARE    OF    THE    BREATHING    ORGANS. 

Need  of  Heat. — No  animal  can  live  without  regularly 
taking  oxygen  into  its  lungs.  About  one  fifth  of  the 
bulk  of  common  air  is  oxygen,  and  this  is  just  the  right 
proportion  for  breathing  purposes.  When  common  air  is 
drawn  into  the  lungs  the  oxygen  is  pulled  through  the  thin 
walls  of  the  air  sacs  and  the  capillaries  by  the  corpuscles, 
and  carried  by  them  all  over  the  body.  The  corpuscles 
are  as  ready  to  give  it  up  as  they  are  to  take  it.  The 
tissues  need  it  in  order  to  rebuild  themselves,  and  so  all 
over  the  body  oxygen  is  constantly  changing  its  place, 
and  when  it  unites  with  any  tissue  it  produces  heat  or 
motion  force. 

Heat. — By  this  changing  action  which  takes  place  in 
the  capillaries,  the  heat  of  the  entire  body  is  kept  about 
99°.  If  there  is  a  variation  of  two  degrees  either  way, 
there  is  sickness.  Generally  the  body  temperature  is 
higher  than  that  of  outside  air.  People  get  very  uncom- 
fortable when  the  thermometer  marks  anything  near  100°, 
because  the  extra  heat  of  the  body  cannot  be  radiated, 
or  given  off',  to  air  that  is  about  the  same  heat  as  the 
body. 

Sometimes  one  part  of  the  system  works  faster  than 
the  rest,  and  gets  warmer,  as  the  muscles  of  the  legs 
when  we  walk.  A  great  deal  of  heat  is  produced  by  the 
exertion  of  walking,  and  the  muscles  get  warmed  up;  but 
the  blood,  hurrying  along,  takes  much  of  the  heat  away  to 
other  portions  of  the  body.  This  is  part  of  the  reason 
why  walking  warms  the  whole  system. 

Blood,  besides  carrying  food  and  oxygen  to  all  parts, 
acts  as  a  regulator  of  temperature.  For  example,  if  the 


CARE  OF  THE  BREATHING  ORGANS.  209 


surface  of  the  body  gets  chilled,  the  blood  hurries  in  to 
warmer,  or  working,  parts  to  get  warm,  and  warmer  blood 
goes  to  the  surface,  and  with  proper  care  the  whole  body 
is  thus  kept  comfortable. 

Carbon  Dioxide. — In  the  burning  of  tissues  a  bad 
gas  is  formed,  which  the  blood  carries  off  to  the  lungs  and 
skin,  where  it  is  exhaled.  It  is  called  carbon  dioxide,  or 
carbonic  acid  gas,  which  means  that  it  is  made  of  two 
parts  of  oxygen  and  one  part  of  an  element  called  carbon. 
It  is  this  gas  in  expired  air  that  puts  out  a  candle  and 
turns  lime  water  white  (see  p.  110).  It  is  a  colorless 
gas,  without  odor  or  taste,  and  these  characteristics  make 
it  more  dangerous,  because  we  cannot  detect  it  in  the  air 
by  sight,  smell,  or  taste. 

When  inhaled  in  large  quantities  it  is  suffocating,  but 
not  poisonous,  and  it  prevents  breathing,  not  so  much  by 
destroying  tissues,  as  poisons  do,  as  by  crowding  away 
oxygen,  for  even  two  gases  cannot  fill  the  same  place  at 
the  same  time. 

Being  heavier  than  air,  it  sinks  down  in  wells  and 
collects  in  low  levels  of  mines,  and  often  suffocates  men 
at  work  there.  Miners  call  it  "choke  damp." 

Carbon  dioxide  is  formed  by  the  breathing  of  all  ani- 
mals, by  decay  and  burning,  and  is  present  in  varying 
quantities  in  air.  Plants  use  it  up.  They  take  it  in 
somewhat  as  we  take  in  air,  and  in  their  tissues  they 
break  it  up,  and,  keeping  the  carbon  for  their  own  use, 
they  give  out  the  oxygen.  Thus  plants  supply  animals 
with  oxygen,  and  animals  are  always  forming  the  carbon 
dioxide  which  plants  need.  Even  in  aquariums,  the 
small  animals  would,  by  breathing,  soon  fill  the  water  so 
full  of  this  gas  that  they  would  all  suffocate,  and  for  this 
reason  some  water  plants  are  put  in  to  use  up  carbon 
dioxide,  and  to  supply  oxygen. 


210  HYGIENE. 

Organic  Matter. — Besides  carbon  dioxide  the  expired 
air  contains  organic  matter  in  invisibly  fine  particles, 
which  acts  something  like  poison.  It  is  the  most  danger- 
ous part  of  expired  air.  This  organic  matter  is  the  waste 
material  from  tissues,  and  is  impure  and  foul  even  com- 
ing from  healthy  lungs,  but  when  it  conies  from  diseased 
lungs  and  bodies  it  is  often  the  source  of  contagious  dis- 
eases. Sometimes  people  forget,  or  do  not  know,  that  it 
is  as  necessary  to  breathe  pure  air,  and  plenty  of  it,  as  it 
is  to  eat  good  food.  The  breathing  organs  are  often 
wronged  in  two  ways:  by  tight  lacing  and  by  breathing 
bad  air. 

Effect  of  Bad  Air. — If  there  are  foul  gases  in  the 
air,  or  if  the  air  has  been  rebreathed  several  times  by 
people  in  a  close  room,  the  blood  does  not  get  a  proper 
amount  of  oxygen,  and  so  keeps  its  carbonic  acid  gas  and 
organic  materials,  and  goes  circulating  with  them  among 
the  tissues.  This  is  what  causes  people  to  feel  dull  and 
drowsy,  or  to  have  a  headache,  or  to  faint  in  a  crowded 
room.  Daily  breathing  of  bad  air  causes  lung  diseases, 
-a  kind  of  oxygen  starvation.  Outside  air  is  changing 
constantly  and  is  mixed  by  the  wind  and  heat,  but  air 
in  the  houses  is  apt  to  be  heavy  and  impure. 

Ventilation. — Making  arrangements  to  drive  bad  air 
out  and  admit  pure  air  into  houses  is  called  ventilation. 
It  is  a  subject  that  deserves  more  thought  than  it  gen- 
erally receives.  The  great  trouble  is  to  avoid  a  draft 
while  getting  pure  air.  In  most  parts  of  California  the 
matter  is  more  easily  settled  than  in  places  where  there 
is  extreme  cold.  There  are  two  good  rules  to  follow  in 
ventilation:  first,  see  that  no  sewer  gas,  or  impure  air 
from  drains,  can  enter  the  house;  second,  keep  the  win- 
dows open,  day  and  night,  as  much  as  possible. 

In  schools  the  frequent   recesses   give   the  teacher  a 


CARE  OF  THE  BREATHING  ORGANS.  211 

chance  to  open  the  windows  and  allow  the  air  to  change. 
In  winter  a  good  fire  should  be  made,  all  the  windows 
opened  for  a  few  minutes  to  drive  out  bad  air  and  let  in 
good,  and  then  the  windows  should  be  closed,  except  a 
small  opening  at  the  top,  and  the  cold  air  warmed  up 
before  the  children  come  in  from  play.  In  the  rainy 
season  the  windows  can  be  thrown  wide  open,  and  the 
children  take  exercise  in  light  gymnastics  while  the  room 
is  being  ventilated  and  is  getting  back  to  a  comfortable 
temperature. 

A  room  that  is  used  much  should  be  frequently  aired, 
or  there  should  be  some  way  of  having  the  air  constantly 
circulating.  This  is  especially  true  of  sleeping  rooms. 
Open  fireplaces,  or  ventilators  connected  with  heated 
chimneys,  are  excellent  means  of  ventilation. 

The  temperature  of  air  has  nothing  to  do  with  the 
amount  of  oxygen  it  contains.  Cool  air,  that  is  con- 
sidered comfortable,  in  a  shut  up  house  in  summer  may 
be  dead,  stagnant,  and  nearly  destitute  of  oxygen;  while 
air  from  the  outside,  in  winter,  that  has  been  warmed  on 
its  way  into  a  house,  will  have  all  the  needed  oxygen. 
Oxygen  is  the  necessary  part  of  air,  and  it  is  not  made 
inside  of  houses.  The  practice  of  shutting  windows  in 
summer  to  keep  rooms  cool,  and  to  keep  out  the  hot  air,  is 
as  bad  as  shutting  them  in  winter  to  keep  out  cold  air. 
Excessive  sunlight  and  severe  cold  can  and  must  be  kept 
out,  but  oxygen  must  get  in.  Outside  air  is  better  than 
house  air  under  almost  any  circumstances,  and  inside  air 
can  generally  be  kept  warm  and  pure  in  winter,  and 
cool  and  pure  in  summer,  if  people  will  spend  the  time 
and  thought  on  ventilation  that  health  requires. 

Sensitiveness  to  impure  air  ought  to  be  taught  in 
school.  One  has  only  to  go  from  out-doors  into  a  room 
that  has  been  filled  a  short  time  with  people,  or  a 
sleeping  room  that  has  been  occupied  with  the  windows 

14— P 


212 


HYGIENE. 


5, 

a 


CARE  OF  THE  BREATHING  ORGANS. 


213 


A 

i 


214  HYGIENE. 

shut  to  keep  out  night  air,  to  appreciate  the  foulness  of 
expired  or  dead  air.  People  in  such  rooms  do  not  notice 
its  badness,  for  the  system  gets  used  to  it,  and  does  not 
give  any  warning  until  the  tissues  are  starved  and  stu- 
pefied, and  then  come  headache,  dullness,  sleepiness,  or 
nausea  and  faintness. 

There  are  cases  where  people  have  died  quickly  from 
bad  air  when  a  number  were  crowded  in  a  small  room. 
In  Calcutta,  in  1756,  one  hundred  and  forty-six  English- 
men were  imprisoned  in  a  room  that  was  eighteen  feet 
square,  and  had  only  two  windows.  One  hundred  and 
twenty  died  during  the  night.  In  1857,  an  English  offi- 
cer shut  two  hundred  and  eighty  Sepoys  in  a  round  tower, 
and  forty -three  died  during  the  night.  These  are  extreme 
cases,  but  there  are  others  like  them  where  strong  men, 
as  prisoners,  have  died  immediately,  or  in  a  few  days, 
from  breathing  bad  air;  but,  generally,  the  harmful 
effects  are  slow  to  show  themselves,  and  the  diseases 
they  produce  are  not  traced  back  to  their  cause. 

Compressing  the  Chest. — With  a  world  full  of  pure 
air,  a  woman  with  her  lungs  crushed  together  by  tight 
corsets  cannot  get  enough  air  to  keep  her  healthy.  Dif- 
ferent nations  have  different  ways  of  deforming  them- 
selves. The  Chinese  children  of  the  higher  classes  have 
their  feet  crushed  into  a  mold,  so  that  they  cannot 
develop,  and  the  ladies7  feet  are  thus  made  to  look  some- 
thing like  cows'  feet.  The  Flat-head  Indians  tie  boards 
to  the  heads  of  babies,  and  squeeze  the  skull  out  of  shape. 
Civilized  people  sometimes  put  corsets  on  the  girl  chil- 
dren, to  squeeze  the  flexible  ribs  in  on  the  soft  organs, 
and  make  wasp-like  waists.  One  result  is  just  as  fash- 
ionable and  pretty  as  the  other,  but  the  waist  deformity 
is  most  injurious,  because  it  crowds  the  vital  organs  out 
of  place,  and  causes  disease. 


CARE  OF  THE  BREATHING  ORGANS. 


215 


FIG.  86  (Copied).  Deformed  Waist,  with  organs  pressed  out  of  posi- 
tion.   Dotted  lines  give  normal  size  of  waist  and  position  of  organs. 

Fortunately,  tight  lacing  is  going  out  of  fashion,  and 
before  long  an  extremely  small  waist  will  indicate  a  per- 
son of  ignorance,  or  bad  taste.  Compare  Fig.  84,  which 
is  taken  from  a  celebrated  Greek  statue,  in  which  the 
proportions  are  considered  perfect,  and  Fig.  85,  from  a 
recent  fashion  plate.  A  study  of  Figs.  84  and  85  will  be 
profitable  for  any  one  who  wants  to  know  what  tight 
lacing  does.  Fig.  86  shows  the  position  of  organs  in  the 
trunk  cavity,  and  how  closely  they  are  packed  together. 
The  dotted  lines  show  the  normal  shape  of  the  body  and 


216  HYGIENE. 

position  of  organs,  and  the  strong  lines  show  the  position 
organs  assume  when  the  waist  is  squeezed  in. 

Effect  of  Pressure. — Normally  the  organs  are  smooth, 
and  closely  packed  in  the  trunk,  and  they  move  easily  on 
one  another  in  the  motions  of  respiration  and  digestion. 
When  pressed  they  must  go  somewhere,  and  they  crowd 
each  other;  for  as  the  trunk  does  not  increase  in  size,  the 
objects  it  contains  must  pack  more  closely  together,  their 
cells  are  crowded,  and  none  of  the  organs  have  room 
enough  for  natural  motion. 

Sometimes  a  woman  has  an  increase  of  fat,  and  tries 
to  lace  it  down,  instead  of  getting  rid  of  it,  if  she  does 
not  want  it,  by  careful  diet  and  exercise.  Lacing  fat 
makes  matters  worse,  for  this  inert  material  wrapped 
around  the  organs  takes  up  the  room,  and  helps  crush 
the  vital  organs  out  of  shape,  and  interferes  with  their 
functions. 

One  has  only  to  remember  that  the  lungs  are  two  elas- 
tic cavities  filled  full  of  delicate-walled  sacs,  that  dilate 
and  relax,  as  the  air  goes  in  and  out,  under  pressure  of  the 
ribs  and  diaphragm;  and  then  to  imagine  multitudes  of 
the  poor  little  cells  crushed  in  by  the  bony  walls  of  the 
chest,  with  their  walls  pressed  together  so  tightly  that  no 
air  can  enter,  and  he  easily  understands  how  tight  lacing 
can  produce  lung  disease. 

Dyspepsia,  heart  and  lung  diseases,  and  sluggish  cir- 
culation are  caused  by  compressing  the  chest,  and  many 
headaches,  poor  appetites,  and  ill  tempers  would  be  pre- 
vented, if  some  people  were  not  just  as  silly  as  the  Chi- 
nese and  the  Flat-headed  Indians. 

The  Pneumo-Gastric  Nerve. — There  is  a  large 
cranial  nerve  that  goes  down  to  the  chest  and  sends  its 
branches  to  the  stomach,  heart,  and  lungs,  and  has  con- 
trol over  their  action.  It  has  something  to  do  with  the 


CARE  OF  THE  BREATHING  ORGANS.  217 

feeling  of  nausea  and  faintness  caused  by  disagreeable 
odors  and  horrible  sights.  The  paralysis  of  this  nerve, 
and  some  others  connected  with  it,  causes  the  serious  and 
sometimes  fatal  result  produced  by  a  blow  on  the  stom- 
ach. Since  it  passes  down  from  the  skull  through  the 
canal  of  a  part  of  the  neck  vertebrae,  any  dislocation  or 
injury  of  the  upper  portion  of  the  neck  is  liable  to  press 
bones  against  it  and  paralyze  it,  thus  causing  immediate 
cessation  of  respiration  and  heart  action. 

To  this  is  due  the  instantaneous  effects  of  hanging,  and 
it  is  the  reason  why  a  broken  neck  is  apt  to  be  more  fatal 
than  the  breaking  of  any  other  part  of  the  spinal  column. 

Diseases  of  Lungs  and  Throat. — The  delicacy  of 
the  mucous  membrane  of  nose,  throat,  and  air  sacs, 
makes  these  parts  subject  to  disease.  Many  of  the 
throat  and  lung  diseases  might  be  prevented -by  proper 
care  about  breathing  pure  air,  and  avoiding  exposure  to 
cold  and  wet.  Some  of  these  diseases  are  inherited,  but 
it  does  not  follow  if  a  person  comes  of  a  consumptive  or 
weak-lunged  family  that  he  must  suffer  with  or  die  of 
lung  disease.  It  is  possible  to  increase  the  lung  capacity 
by  breathing  exercises,  to  avoid  breathing  bad  air,  and  so 
to  care  for  diet,  clothing,  and  general  hygiene  as  to  make 
naturally  unhealthy  lungs  healthy,  and  thus  escape 
hereditary  disease.  The  habits  that  make  persons  sick 
are  inherited,  or  learned  early,  and  these  habits  have  as 
much  to  do  with  health  as  have  the  peculiarities  of  the 
body  with  which  we  are  born. 

Tobacco. — Any  form  of  tobacco  is  an  irritant  to  the 
mucous  membrane.  Ordinary  smoke  makes  the  eyes 
smart,  but  the  smoke  of  tobacco  has  a  greater  stinging 
power.  Tobacco  is  chewed,  smoked,  or  inhaled  as  a 
powder  called  snuff,  and  in  all  cases  comes  first  in  contact 
with  the  mucous  membrane.  It  causes  inflammation 


218  HYGIENE. 

and  final  hardening.  In  the  nasal  passages  the  mem- 
brane gets  thicker  and  interferes  with  the  nerve  of  smell, 
and  induces  a  disease  of  the  membrane  called  smoker's 
catarrh.  Sometimes  the  lips  and  throat  become  sore  from 
use  of  tobacco,  and  the  disease  is  called  smoker's  cancer. 

Alcohol. — Alcohol  injures  the  lung  tissue,  because  of 
its  power  of  absorbing  water  and  increasing  connective 
tissue.  It  hardens  the  cells.  Unfortunately,  no  one  ever 
takes  beer  and  whisky  in  microscopic  doses,  but  micro- 
scopic parts  of  the  body  are  those  they  act  on:  the  air 
sacs,  the  liver  cells,  the  muscle  cells,  and  the  cellular 
walls  of  the  lungs  and  throat  and  stomach. 

Exposure  to  Wet  or  Cold. — By  careless  exposure 
the  vessels  of  the  skin  become  contracted,  and  waste  mat- 
ter cannot  be  exhaled.  The  lungs  try  to  do  the  extra 
work  and  sometimes  succeed.  Other  times  they  are  over- 
taxed and  become  congested  and  inflamed.  The  first 
thing  to  do  after  exposure  is  to  rub  the  body  well,  to  get 
up  a  glow  and  start  perspiration. 

Bad  Air. — Bad  air  is  the  source  of  many  diseases. 
Air  may  be  bad  from  two  causes:  it  may  have  too  little 
oxygen,  or  it  may  contain  injurious  substances,  either 
dust  or  germs. 

If  it  has  too  little  oxygen  the  blood  goes  back  to  the 
body  blue  and  unwholesome.  This  kind  of  bad  air  is 
oftenest  found  in  un ventilated  houses.  Dust  in  the  air 
causes  irritation  of  the  air  passages.  Then  such  workmen 
as  weavers,  grinders,  miners,  millers,  hatters,  and  cigar 
makers,  who  spend  most  of  their  time  in  places  where 
there  is  much  dust  flying,  breathe  in  the  fine  particles 
and  are  liable  to  throat  and  lung  diseases.  This  kind  of 
bad  air  is  found  in  shops,  mines,  and  factories. 

Germ  and  Contagious  Diseases. — But  the  worst 


CARE  OF  THE  BREATHING  ORGANS.  219 

kind  of  bad  air  is  that  which  contains  poisons,  or  germs. 
Germs  are  microscopic  forms  of  life  that  float  in  air  or  in 
water,  and  many  of  them  when  they  get  into  the  human 
system  cause  serious  diseases.  It  is  not  settled  that  most 
of  the  serious  contagious  diseases,  that  are  called  germ 
diseases,  are  really  caused  by  live  germs.  Some  believe 
they  are  caused  by  poison  in  the  air.  But  whether  it  is 
a  poison  or  a  germ,  it  is  surely  in  the  air  and  water,  and 
as  surely  is  produced  by  filth  that  should  have  been  deeply 
buried  or  burned. 

About  eighteen  fevers  and  other  diseases  are  traced  to 
this  source,  and  about  six  of  them  are  contagious  and 
are  the  worst  scourges  of  the  human  race.  Cholera, 
small-pox,  yellow  fever,  diphtheria,  typhoid  fever,  and 
scarlet  fever  are  some  of  these  diseases.  The  germs,  or 
poisons,  are  breathed  in  with  the  air,  and  if  a  person  is 
in  a  condition  to  take  the  disease,  disorders  begin  in  the 
functions  of  the  different  organs.  So,  in  the  first  place, 
the  condition  of  the  person's  body  makes  him  liable  to  dis- 
ease or  able  to  resist  it;  and  this  power  that  some  have  of 
resisting  contagion  is  the  reason  that  every  one  does  not 
perish  in  an  epidemic.  People  of  careless  and  intem- 
perate habits  are  the  first  to  be  affected. 

As  there  is  a  material,  no  matter  how  small,  that  causes 
these  results,  this  material  can  be  carried  in  clothing, 
bedding,  and  on  crockery,  spoons,  and  wall  paper  used 
in  the  sick  room.  In  case  of  any  of  the  diseases  named, 
clothing,  bedding,  wall  paper,  and  all  fabrics  used  about 
the  patient  should  be  burned,  and  the  crockery  and  cut- 
lery should  be  destroyed  or  thoroughly  washed  with 
disinfectants.  A  disinfectant  is  something  used  to  purify 
from  contagious  matter.  It  should  be  of  a  kind  that 
kills  the  germ,  or  destroys  the  poison.  Burned  sulphur, 
sulphate  of  iron,  and  carbolic  acid  are  disinfectants. 

The  less  frequent  occurrence  of  epidemics  among  civ- 


220  HYGIENE. 

ilized  people,  and  the  fact  of  many  of  these  diseases 
originating  among  ignorant  and  filthy  people  in  modern 
times,  show  that  the  greater  care  of  modern  people  for 
hygienic  conditions  is  a  check  to  contagious  diseases. 
Carelessness  about  drains,  cesspools,  stables,  and  slops 
that  may  pollute  the  air  and  drinking  water,  and  the 
keeping  of  rotting  vegetables  in  dirty  cellars,  are  the  ori- 
gin of  many  serious  epidemics  that  are  sometimes  called 
mysterious. 

Effect  on  Other  Systems. — Although  the  diseases 
come  from  the  air,  it  does  not  follow  that  they  confine 
their  effects  to  organs  of  respiration.  They  cause  derange- 
ment of  functions  of  all  organs.  Many  fevers  have  for 
cause,  after  the  bad  air  is  taken  in,  a  derangement  of  the 
sympathetic  nervous  system.  Diseases  of  the  lungs  and 
air  passages  more  often  come  from  irritants  and  want 
of  oxygen  in  the  air  and  excess  of  coldness  than  from 
exposure  to  germs  or  poisons.  The  common  forms  of 
disease  of  the  breathing  organs  affect  the  mucous  mem- 
brane of  all  parts,  the  tissue  of  the  lungs,  and  the  serous 
membrane,  or  pleura. 

DISEASES  OF  THROAT  AND  LUNGS,  AND  CAUSES.    . 

Catarrh  is  an  inflammation  of  the  mucous  membrane  of 

nasal  passages,  caused  by  exposure  to  damp  and  cold; 

inhaling  dust;  the  use  of  tobacco. 
Sore  throat  is  an  inflammation  of  the  membrane  of  the 

throat,  caused  by  exposure. 
Bronchitis  is  an  inflammation  of  the   bronchial  tubes, 

caused  by  exposure  to  changes  of  climate. 
Chronic  bronchitis  is  caused  by  exposure  and  by  the  use 

of  alcoholic  liquors. 
Pneumonia  is  a  disease  that  thickens  the  walls  of  the  air 

cells,  caused  by  exposure  and  alcoholic  liquors. 


CARE  OF  THE  BREATHING  ORGANS.  221 

Congestion  of  the  lungs  is  an  excessive  fullness  of  capil- 
laries of  air  cells,  caused  by  over  exertion,  excitement, 
exposure  to  hot  or  cold  air,  alcohol,  and  Bright's  dis- 
ease of  the  kidneys. 

Consumption  is  a  disease  of  cells  that  destroys  lung  tis- 
sue, and  is  generally  inherited. 

Pleurisy  is  a  disease  of  the  pleura,  called  "  stitch  in  the 
side."  When  acute,  it  is  caused  by  exposure  or  mus- 
cular exertion. 

Chronic  pleurisy  is  caused  by  alcohol  and  Bright's  dis- 
ease, or  is  the  result  of  acute  pleurisy. 


HYGIENE. 

CHAPTER   9. 

CARE    OF    THE    ORGANS    OF    THE    SPECIAL    SENSES. 

Dulled  by  Want  of  Exercise. — The  special  senses 
are  generally  more  acute  in  savages  and  in  the  lower  ani- 
mals than  they  are  in  civilized  men,  because  the  procur- 
ing of  food  and  the  protection  against  enemies  in  these 
cases  depend  on  personal  quickness.  Their  dullness  in 
civilized  people  is  an  example  of  loss  of  power  through 
want  of  exercise. 

The  senses  serve  as  protectors.  They  teach  people 
what  things  are  injurious  to  touch,  taste,  smell,  hear,  and 
look  at.  If  their  warnings  are  heeded,  they  keep  on 
noticing  objectionable  things,  but  if  their  cautions  are  not 
attended  to,  they  soon  cease  to  give  any  unpleasant  im- 
pressions of  particular  smells,  tastes,  sounds,  and  sights, 
and  they  are  then  said  to  become  tolerant. 

This  toleration,  or  stupidity,  often  causes  disease  of 
other  organs. 

Affected  by  General  Diseases. — The  senses  are 
affected  by.  general  disease,  and  the  partial  failure  of 
some  sense  is  often  the  first  sign  of  some  deeper  seated 
disorder.  This  is  especially  true  of  affections  of  the  nerv- 
ous system.  General  rules  of  hygiene,  as  to  cleanliness, 
air,  and  proper  food,  apply  equally  to  organs  of  special 
sense  as  to  general  organs  of  the  system.  There  are  a  few 
particular  directions  for  the  care  of  special  senses. 

Effect  of  Irritants. — Anything  that  irritates  the 
mucous  membrane  disturbs  the  nerve  which  it  holds. 
This  is  true  of  tobacco,  spices,  and  strong  medicines, 
which  deaden  the  sense  of  taste  and  smell.  Some  of 
them  injure  hearing  and  eyesight  as  well.  Exposure  to 
cold  and  wet  inflames  the  membrane  of  the  nose,  mouth, 


CARE  OF  THE  ORGANS  OF  THE  SPECIAL  SENSES.     223 

ears,  and  eyes,  and  often  causes  dullness  of  taste,  smell, 
hearing,  and  sight.  The  organs  of  hearing  and  sight  are 
too  delicate  to  be  interfered  with.  If  deafness  is  caused  by 
a  swelling  in  the  throat  that  closes  the  tube  leading  from 
the  middle  ear  to  the  throat,  then  it  will  pass  away  when 
the  swelling  goes  down.  If  it  is  caused  by  an  accumula- 
tion of  ear  wax  in  the  outer  ear,  great  care  should  be 
taken  to  get  it  out.  Never,  under  any  circumstances, 
scrape  the  ears  with  pins  or  hard  objects,  for  they  are  apt 
to  injure  the  tympanic  membrane.  Use  soft  cloths  and 
warm  water. 

Care  of  Eyes. — There  are  a  number  of  ordinary  de- 
fects of  vision  which  should  be  referred  to  an  eye  doctor 
as  soon  as  they  are  detected.  These  are  shortness  of 
sight,  or  any  difficulty  of  seeing  that  causes  a  strained 
feeling,  or  any  pain  of  the  eyes,  or  a  dimness  of  sight. 
No  one  should  doctor  his  own  eyes,  or  allow  an  ordinary 
physician  to  do  so,  for  there  is  danger  of  causing  a  more 
serious  injury.  Nor  should  a  person  attempt  to  fit  him- 
self with  spectacles. 

The  best  condition  of  mind  in  regard  to  the  eyes  and 
ears  is  ignorance  of  all  eye  and  ear  diseases,  and  a  firm 
conviction  that  the  first  defects  or  pains  of  these  organs 
must  be  referred  to  an  aurist  or  oculist.  Nothing  should 
be  done  that  causes  a  strain  to  the  eyes. 

The  habit  of  bending  the  head  close  to  the  book  in 
studying  or  reading  has  two  evils.  It  induces  near- 
sightedness,  because  the  eyes  are  too  near  the  object,  and 
it  causes  the  humors  of  the  eye  to  press  forward  and  the 
blood  to  accumulate  in  the  face. 

When  there  is  an  unsteady  motion  or  a  flickering  light, 
the  crystalline  lens  and  the  iris  and  muscles  cannot  ad- 
just themselves  to  the  rapid  changes,  and  in  their  effort 
to  do  so  they  cause  a  temporary  strain,  or  perhaps  a  per- 
manent injury. 


224 


HYGIENE. 


THINGS  TO  AVOID. 


Irritants. 

Exposure  to  heat,  co'ld,  or  ex- 
cessive sunlight. 

"Using  hard  objects  for  cleaning 
the  ears. 

Putting  cotton  in  the  ears. 

Boxing  the  ears. 

Putting  liniments  in  the  ears. 

Studying  or  reading  with  the 
head  bent. 


Studying  with  strong  light  in 

the  eyes. 

Studying  when  lying  down. 
Studying  on  cars  or  where  there 

is  unsteady  motion.  - 
Studying  with  book  near  the 

eyes. 

Using  unknown  eye  lotions. 
Using  the  eyes  for  fine  work  at 

twilight  or  in  badly  lighted 

rooms. 


CARE  OF  THE  NERVOUS  SYSTEM.  225 

CHAPTER   10. 

CARE    OF    NERVOUS    SYSTEM. 

No  part  of  the  body  is  independent  of  the  rest;  and  the 
brain,  its  ruler,  is  seriously  affected  by  a  disorder  of  any 
of  the  systems. 

Needs  of  the  Brain. — All  the  brain  needs  is  good  food 
to  nourish  it;  good  red  blood  to  oxidize  its  tissue;  good 
impressions  and  thoughts  to  stimulate  its  growth;  and 
good  rest  to  recreate  its  tissues,  and  then  it  promises 
good  results  in  healthy  physical  and  mental  manhood  or 
womanhood.  Fortunately,  the  good  things  for  the  brain 
are  within  the  reach  of  all. 

Facts  to  Remember. — In  order  to  take  proper  care 
of  the  nervous  system,  a  number  of  facts,  some  of  them 
often  forgotten  by  Americans,  must  be  recollected: 

1.  Brain  is  material,  capable  of  being  acted  on  by 
material,  but  originating,  as  a  high  product,  an  immate- 
rial something,  called  thought. 

2.  The  nervous  system  of  a  baby  has  to  be  taught 
before  it  can  control  the  body. 

3.  The  nervous    systems  of  children  are  busier  than 
those  of  grown  people,  in  controlling  additional  growth 
and  learning,  thought  and  action. 

4.  The  brains  of  children  have  fewer  convolutions,  that 
is,  less  gray  matter  and  less  thought  and  motive  power. 

5.  Habits  are  signs  of  the  way  the  nervous  system  has 
learned  to  act. 

6.  Knowledge  is  a  result  of  brain  experience. 

7.  The  experience  of  children  is  limited. 

8.  Their  judgment  of  important  matters  of  diet  and 
hygiene  is  not  to  be  relied  on. 

Material  for  Brain  Building. — The  nervous  system, 


226  HYGIENE. 

like  any  other,  needs  good  food  and  pure  air  for  rebuild- 
ing its  tissue.  It  is  not  necessary  to  eat  special  brain 
food,  for  any  food  that  will  nourish  the  general  system 
will  build  up  the  brain.  The  amount  of  blood  that  goes 
to  the  brain  is  an  indication  of  the  amount  of  work  done. 
If  nourishing  food  in  sufficient  quantity  is  not  taken,  there 
is  faintness;  if  too  much  food  is  constantly  taken,  or  if 
it  is  mixed  with  injurious  articles,  or  if  the  blood  has 
not  enough  oxygen,  there  is  stupor  and  dullness. 

Injury  to  the  Brain. — Certain  stimulants  and  nar- 
cotics act  on  nerve  material,  and  destroy  the  function  of 
the  brain.  Brain  tissue  may  not  be  any  more  seriously 
injured  by  these  things  than  other  parts  are,  but  the  conse- 
quences are  more  vital.  Alcohol  has  a  destructive  action 
on  the  brain  and  nerves,  in  increasing  the  connective 
tissue  and  in  causing  fatty  degeneration;  but  long  before 
these  extreme  effects  begin,  in  fact,  on  the  very  first  dose, 
alcohol  stimulates,  and  then  deadens  or  stupefies  the 
nerves.  This  last  action  is  shown  by  secondary  effects  on 
the  other  organs. 

When  a  glass  of  alcoholic  liquor  is  taken  by  one  not 
used  to  it,  the  face  gets  red  and  warm.  This  means  that 
the  liquor  affects  the  nervous  system,  so  that  the  small 
nerves  which  control  the  capillaries  cannot  act,  and  the 
capillaries  become  filled  with  warm  red  blood,  which 
shows  red,  and  can  be  felt  warm  on  the  surface. 

Sometimes,  if  much  is  taken,  there  is  a  feeling  of  faint- 
ness  and  nausea,  and  the  large  cranial  nerve  that  goes 
down  to  the  stomach  tries  to  get  up  enough  disturbance 
to  cause  the  injurious  liquid  to  be  thrown  off  by  vomiting. 
Other  nerves  are  stimulated,  and,  with  some  people,  the 
cerebrum  is  more  active  for  a  time,  and  with  others,  it  is 
more  stupid;  but  it  soon  begins  to  act  in  a  confused  and 
irregular  manner.  Thoughts  are  crowded  and  uncertain, 
and  the  man  has  ideas  and  impulses  that  would  never 


CARE  OF  THE  NERVOUS  SYSTEM.  227 

occur  to  him  when  he  was  sober.  The  will  power  and 
common  sense  power  that  come  from  experience  seem 
paralyzed,  and  his  impressions  of  common  objects  and 
judgments  of  his  best  friends  are  distorted,  uncertain,  and 
unnatural. 

The  cerebellum,  which  controls  muscular  action,  loses 
its  power,  and  at  first  there  is  an  irregular  and  spasmodic 
action,  a  staggering  and  tottering,  and  then  the  person 
falls  dead  drunk,  powerless  and  unconscious.  It  is  diffi- 
cult to  say  which  is  the  more  pitiable  sight,  the  stage  of 
silliness  and  spasmodic  action  of  thought  and  motion,  or 
the  stage  of  complete  paralysis. 

It  would  seem  as  though  nerve  matter  acted  with  alco- 
hol much  as  some  animal  does  in  the  grasp  of  a  powerful 
enemy,  struggling  fearfully  until  completely  overpowered. 

Narcotics,  like  opium,  do  not  excite  the  person  to  deeds 
of  mad  violence  as  alcohol  sometimes  does.  They  sooner 
envelop  him  in  unconsciousness.  Like  alcohol  they 
destroy  will  power,  at  first,  without  taking  away  con- 
sciousness, and  the  consequence  is  that  the  sense  of  time 
and  place  and  personality  is  changed  and  the  mind  is 
filled  with  fantastic  ideas.  These  ideas  are  by  no  means 
always  as  pleasant  as  is  commonly  supposed.  Sometimes 
they  are  as  horrible  and  terrifying  as  bad  dreams.  Before 
the  stupor  comes  that  follows  the  taking  of  narcotics,  the 
slave  to  them  may  undergo  fearful  mental  torture. 

Neither  opium  nor  alcoholic  preparations  act  at  first 
the  same  on  all  persons,  but  their  final  results  are  mer- 
cilessly the  same  for  all  men  in  deranging  functions  of 
organs,  and  in  destroying  moral  sense  and  will  power. 

The  effect  that  stimulants  and  narcotics  have  on  the 
will  and  morals  of  people  is  the  worst  thing  about  these 
terrible  drugs.  Physical  slavery  is  bad,  but  a  mental 
and  moral  slavery  that  is  brought  on  by  personal  weak- 
ness is  the  most  terrible  form  of  servitude. 

15— P 


228  HYGIENE. 

Exercise. — The  brain  can  increase  its  capacity  for 
work  by  exercise,  just  as  the  lungs  and  muscles  can  in- 
crease theirs,  and  it  can  also  become  almost  useless  by 
want  of  exercise.  Thought  and  study  are  the  exercise  of 
the  brain.  Thinking  makes  the  power  to  think.  Certain 
parts  of  the  brain  can  be  used  to  the  injury  of  others, 
as  when  a  person  educates  his  business  or  musical  facul- 
ties at  the  expense  of  the  rest,  so  that  his  judgment  of 
anything  out  of  his  line  of  thought  is  as  unreliable  as 
that  of  a  child. 

Fatigue. — After  a  person  has  been  working  or  study- 
ing hard  there  comes  a  time  of  weariness,  if  the  work  is 
continued;  even  after  a  short  pause  to  take  fresh  air  and 
food  there  is  still  fatigue;  if  stimulants  are  taken  there 
is  a  momentary  rush,  and  then  if  rest  is  not  taken  there 
is  a  break  down.  No  body  or  brain  can  work  continu- 
ously. There  is  a  great  deal  of  intemperate  use  of  both, 
and  the  penalty  falls  heaviest  on  the  nervous  system. 
Some  people  forget  that  the  brain  has  other  functions 
than  that  of  producing  thought.  It  controls  the  volun- 
tary motions  and  a  person  can  get  fatigued,  to  the  point 
of  falling  down,  by  work  that  has  not  developed  a  single 
thought,  and  his  brain  needs  rest  in  such  a  case  just  as 
much  as  though  he  had  exhausted  it  by  mental  calcula- 
tions. 

There  is  considerable  harm  in  the  statement  that 
change  of  work  is  rest.  It  is  true  only  in  the  limited 
sense  that  change  of  work,  within  certain  limits,  is  rest. 
A  person  cannot  work  to  the  point  of  exhaustion  with  his 
muscles  and  then  turn  for  rest  to  severe  mental  labor,  nor 
can  he  get  rest  after  fatiguing  mental  work  by  exhaustive 
muscular  action.  The  strain  is  too  great  and  the  sys- 
tem breaks.  Exhaustion  is  a  call  for  cessation  of  work. 

There  is  a  great  deal  of  talk  about  overtaxing  young 


CARE  OF  THE  NERVOUS  SYSTEM.  229 

people's  brains  by  study.  Very  few  persons  are  intem- 
perate in  the  matter  of  study  alone.  In  most  cases  where 
the  health  of  young  people  is  broken  down  it  will  be 
found  that  they  have  been  trying  to  carry  too  much,  to 
keep  up  habits  of  social  or  other  dissipation,  or  to  carry 
a  load  of  worry  and  fret,  at  the  same  time  they  are  study- 
ing. If  a  person  is  careful  about  hours  of  rest  and  work, 
and  about  general  hygiene,  he  can  do  much  more  brain 
work  than  the  average  student  does,  without  the  slightest 
inconvenience;  but  if  he  adds  to  his  healthy  mental 
effort  the  irritations  of  fashionable  life  and  the  waste 
stimulus  of  fretting,  he  will  be  apt  to  destroy  his  health. 
Fret  and  worry  kill  more  than  work  and  study.  The 
shortening  of  life  is  not  the  commonest  nor  the  worst 
penalty  for  overtaxing  strength.  The  most  deplorable 
effect  is  the  wrecking  of  health,  when  the  victim  of  any 
dissipation  lives  for  years,  broken  in  body  and  mind, 
and  useless  to  himself  or  others. 

Change. — Too  long  continued  work  is  wearying. 
When  studying,  a  person  should  put  all  his  mind  on  the 
work  for  a  short  time,  then  stop,  move  about  to  start  the 
circulation  of  blood  and  get  fresh  air,  then  sit  down  again 
to  hard  study. 

Time  for  Application. — A  child  of  from  six  to  twelve 
years  should  not  study  one  subject  closely  more  than  from 
fifteen  to  twenty  minutes  at  a  time;  and  from  twelve  to 
sixteen  years  not  more  than  twenty  or  thirty  minutes. 
This  means  close  concentration  on  one  subject.  Too  often 
careless,  inattentive,  lazy  work  is  called  study.  To  study 
to  learn  one  must  learn  to  study,  and  close  application  for 
a  short  time  is  what  fixes  ideas  in  the  brain. 

Sleep. — Sleep  is  the  great  restorer.  During  sleep  the 
respiration  and  circulation  are  slower  and,  at  that  time, 
when  the  brain  is  not  constantly  getting  new  impulses, 


230  HYGIENE. 

the  tissues  are  rapidly  repaired.  A  person  should  wake 
up  in  the  morning  bright,  refreshed,  and  clear  headed. 
The  number  of  hours  of  each  day  to  be  spent  in  sleep 
varies  with  occupation  and  individuals,  but  generally 
eight  hours  is  considered  a  good  allowance.  The  use  of 
sleep  is  to  get  rest,  and  when  a  person  is  rested  he  has 
had  enough  sleep.  Under  ordinary  circumstances  a  per- 
son should  be  allowed  to  sleep  till  he  wakes  of  his  own 
accord. 

Sleeplessness. — Sleeplessness,  or  the  inability  to  sleep 
a  proper  number  of  hours,  may  be  caused  by  approaching 
disease,  or  it  may  be  the  effect  of  bad  habits.  If  change  of 
diet,  of  hours  of  eating,  of  ordinary  habits,  or  an  increase 
of  exercise  and  fresh  air  do  not  produce  natural  sleep,  a 
person  must  appeal  to  the  educated  gray  .matter  in  the 
brain  of  some  physician.  Soothing,  or  sleep,  draughts  are 
dangerous. 

Dreams. — Bad  dreams  and  troubled  sleep  are  often 
the  effect  of  bad  digestion,  eating  late  meals  or  not  eating 
regularly,  or  of  bad  respiration  and  circulation.  Dream- 
ing is  not  so  much  a  matter  of  mind  as  of  body,  for  a 
criminal  with  good  digestion  can  sleep  more  sweetly  than 
the  noblest  man  living  who  suffers  with  dyspepsia. 

Sleep  of  Children. — Children  and  young  people  natu- 
rally sleep  more  than  old  people.  Youth  is  the  time  of 
great  tissue  changes.  They  are  getting  larger  bodies  all 
the  time,  and  nothing  should  be  allowed  to  interfere  with 
their  long  hours  of  sleep.  Children  should  never  be 
allowed  to  get  "nervous."  When  irritability  and  ill 
temper  shall  be  considered  physical  ills  to  be  treated  as 
measles  and  stomach  ache,  fewer  people  will  have  to  bear 
the  affliction  of  other  persons'  nerves. 

Simple  diet,  regular  meals,  absolutely  no  stimulant  or 
narcotic  (tea,  coffee,  alcohol,  or  soothing  syrups),  fresh 


CARE  OF  THE  NERVOUS  SYSTEM.  231 

air,  plenty  of  sleep,  and  simple  amusements,  ought  to 
give  an  ordinary  child  a  healthy  body,  and  help  a  sick 
child  to  become  stronger.  These  are  things  that  a  child 
is  not  experienced  enough  to  understand,  and  upon  which 
the  wisdom  of  the  parent  should  insist. 

Habits. — A  child  learns  as  much  from  observing  the 
habits  of  grown  people  as  from  being  taught  ways  of  act- 
ing. A  habit  is  merely  an  easy  way  of  doing  or  think- 
ing, and  it  may  be  a  good  or  a  harmful  way.  It  is  not 
easy  at  first  to  learn  a  habit.  The  brain  is  conscious  of 
something  to  be  done,  but  the  nerve  matter  has  never 
carried  the  impulse  to  do  it  to  a  muscle,  or  learned  the 
way  to  think  that  thought,  and  there  is,  perhaps,  a  re- 
sistance, and  the  new  impulse  has  to  crowd  itself  along 
and  break  its  way. 

The  first  attempt  at  action,  or  thought,  is  as  awkward 
as  a  child's  first  writing,  and  we  say  the  task  is  difficult; 
but  the  second  time  the  impulse  goes  over  the  white  nerve 
road  it  is  easier,  and  by  repetition  each  time  easier,  till 
the  habit  is  learned,  and  then  it  sometimes  happens  that 
something  that  was  learned  with  much  care  and  thought, 
as  walking,  becomes  an  almost  unconscious  action. 

As  with  hand  craft,  so  with  thought  craft,  the  way  has 
to  be  made,  and  then  it  becomes  easy  for  impulses  to  go 
in  certain  directions.  The  day's  thoughts  travel  beaten 
paths,  and  it  is  much  a  matter  of  personal  will  whether 
people  allow  bad  thoughts,  like  wild  beasts,  to  go  raging 
through  their  brains,  or  require  good  thoughts  peacefully 
to  travel  their  own  familiar  pathways.  If,  from  faulty 
training,  or  wrong  surroundings,  impulses  that  a  person 
does  not  want  have  obtained  the  right  of  way,  the  only 
proper  thing  to  do  is  to  start  better  impulses  on  other 
tracks  near  by,  so  that  the  last  impulses  crowd  the  other 
paths  till  there  is  no  thoroughfare  for  the  wrong  impulses. 


232 


HYGIENE. 


Self-control. — The  habit  of  self-control  is  the  most 
important  that  can  be  acquired,  and  it  means  not  only 
control  of  eating  and  drinking  and  physical  acts,  but 
also  of  mental  and  emotional  impulses.  Violent  temper 
is  a  form  of  intemperance  that  not  only  leaves  an  after 
feeling  of  personal  meanness  in  a  right  minded  person, 
but  it  seriously  affects  secretion,  circulation,  and  diges- 
tion. It  is  one  of  the  forms  of  excitement  that  brings 
on  heart  disease. 

Excesses. — Over  study,  over  play,  over  excitement,  in 
fact,  any  physical  and  mental  excess,  injures  the  health 
by  interfering  with  the  comfortable  and  constant  nerve 
function  that  controls  different  organs.  Any  great  strain 
on  the  cerebro-spinal  system  must  be  equalized  by  a  pull 
on  the  other  systems,  and  the  weakest  of  them  always 
gives  away  first,  and  the  secondary  effect  may  not  be 
referred  to  its  proper  cause. 

As  a  person's  health  and  character  depend  on  his 
habits,  and  as  good  habits  are  as  quickly  learned  as  bad 
ones,  it  is  important  that  parents  and  teachers  should 
pay  much  attention  to  the  forming  of  children's  habits. 

That  which  excites  the  nervous  system  of  children  to 
unnatural  action,  such  as  unhealthful  food,  drink,  and 
mental  stimulants,  robs  them  of  some  power  to  regulate 
the  growth  of  the  body,  and  the  result  is  small  bodies, 
or  diseased  bodies  or  minds. 


THINGS  TO  AVOID. 


Bad  air. 
Bad  food. 
Stimulants. 

Excess  in  eating  and  drinking. 
Excitement. 

Excess  in  novel  reading  or  any 
stupefying  brain  work. 


Excess  of  studying  or  mental 
work. 

Formation  of  injurious  habits. 

Exercising  one  set  of  mental  fac- 
ulties at  the  expense  of  others. 

Doing  too  little  brain  work. 

Fret,  worry,  waste  brain  effort. 


CARE  OF  THE  NERVOUS  SYSTEM. 


233 


DISEASES  OF  THE  NERVOUS  SYSTEM. 

Congestion  of  the  brain  is  an  overfullness  of  the  blood 
vessels  of  the  brain.  It  has  many  causes,  and  the  pre- 
ventable ones  are  excess  in  eating  and  drinking,  in  use 
of  alcohol,  and  in  mental  labor. 

Cerebral  fever  is  an  inflammation  of  the  membrane  of 
the  brain,  whose  preventable  causes  are  overworking 
the  brain,  sleeplessness,  and  alcoholism. 

Inflammation  of  the  membranes  and  nerve  matter  of  the 
spinal  cord.  There  are  a*  number  of  diseases  of  the 
spinal  cord  that  are  caused  by  exposure  to  damp  and 
cold,  by  alcohol,  by  injuries,  and  by  other  diseases. 

Neuralgia  is  a  disease  of  the  nerves,  accompanied  with 
acute  pain.  Its  preventable  causes  are  worry,  great 
mental  exertion,  bad  air,  exposure  to  cold  and  damp. 

Paralysis  is  a  suppression  of  the  motor  and  reasoning 
power  of  the  nerves,  and  of  the  function  of  gray  cells. 
It  may  be  partial  or  complete.  It  is  due  to  injury  to 
nerve  centers,  caused  by  escape  of  blood  in  the  brain 
cavity,  pressure  of  blood  vessels,  mineral  poisons  (as 
for  example,  lead),  fibrous  degeneration,  and  injury  to 
spinal  cord. 


NECESSARIES    OF 
LIFE. 


Good  food 

Pure  air 

Regular  exercise    . 

Frequent  baths  .  . 
Moderate  thought. 
Plenty  of  sleep  .  . 


ORGANS    THEY 
AFFECT. 

Alimentary  canal. 

Lungs    

Muscles    . 


Skin  .... 
Brain .... 
All  systems 


THEIR    USE. 

Builds  all  tissues. 

Builds   tissues,    makes  heat. 

Strengthens  muscles  and  in- 
vigorates system. 

Free  pores. 

Develops  gray  matter. 

Rests  and  permits  renewal 
of  tissues. 


234  HYGIENE. 

TESTS  OF  KNOWLEDGE. 

The  models  below  are  to  emphasize  the  dependence  of  sys- 
tems upon  one  another,  and  to  show  the  physical  action  of 
ordinary  injuries,  and  to  test  the  memory  of  the  pupil. 
They  can  be  varied  almost  indefinitely  at  the  will  of  the 
teacher. 

A  bee  stings  the  hand.     What  happens  ? 

Answer. — The  nerve  of  sensation  takes  the  message 
to  the  gray  cells  of  the  brain  and  we  are  conscious  of  pain. 
The  nerve  of  motion  takes  down  an  order  to  the  muscles 
to  contract  and  draw  the  hand  away  from  the  cause  of 
injury.  The  poison  of  the  sting  produces  an  irritation 
of  tissue,  which  brings  to  it  more  than  the  usual  amount 
of  blood,  and  this  causes  heat  and  inflammation;  gorged 
with  blood,  the  tissues  are  enlarged,  making  a  swelling, 
and  the  swelling  presses  against  the  nerve,  making  more 
pain.  This  extra  impression  is  carried  to  the  brain,  and 
the  judgment  of  educated  cells  orders  the  application  of 
lotions. 

A  finger  is  cut.     What  happens  before  it  is  healed  ? 

Answer. — The  sensory  nerve  carries  an  impression  of 
pain  to  the  gray  cells.  The  cerebral  cells,  working  as 
they  have  learned,  order  the  wound  to  be  pressed  or  to  be 
bound  up.  If  the  wound  be  small,  the  blood  soon  coagu- 
lates and  shuts  the  opening.  In  healing  there  is  a  call 
for  forming  material  which  is  circulating  in  the  blood. 
This  tissue  maker  was  manufactured  in  the  stomach  and 
liver,  from  albuminoids.  It  seeped  through  the  walls  of 
the  stomach,  was  reorganized  in  the  liver,  went  to  the 
ascending  vena  cava,  to  the  right  auricle,  right  ventricle, 
pulmonary  artery,  lungs,  pulmonary  veins,  left  auricle, 
left  ventricle^  aorta,  artery  of  the  arm  and  hand,  till  it 
reached  the  capillaries,  and  soaked  through  their  thin 


TESTS  OF  KNOWLEDGE.  235 

walls,  bathing  the  tissues,  and  there  it  mends  the  cut  por- 
tion. If  the  person  is  weakened  by  disease  the  healing 
process  is  slow.  If  some  blood-preparing  organ  is  dis- 
ordered,, then  the  proper  material  is  not  made,  and  the 
wound,  instead  of  healing,  becomes  a  sore.  The  same 
thing  may  happen  by  some  foreign  substance  getting  into 
the  cut  and  poisoning  the  tissues. 

Bone  mending:  The  mending  of  broken  bone  involves 
the  same  nervous  action,  digestion,  absorption,  circula- 
tion, except  that  carbonate  of  lime  taken  in  solution  in 
water  and  in  combination  with  other  foods,  must  be 
added  to  the  proteid  material,  and  the  nerve  cells  of  the 
brain  are  not  able  of  themselves  to  bring  about  a  cure 
without  the  aid  of  a  surgeon. 

A  person  has  studied  till  his  head  aches,  and  his  feet  are  cold. 
How  does  he  change  matters  ? 

Answer. — The  gray  nerve  cells  order  some  active  serv- 
ice. The  motor  nerves  cause  muscles  to  contract.  Con- 
traction produces  heat,  motion,  and  a  demand  for  oxygen. 
The  blood  carries  the  extra  heat  to  different  parts  of  the 
body.  The  demand  for  oxygen  causes  quicker  respiration 
and  circulation.  The  blood  pressure  on  the  brain,  caused 
by  over  study,  that  made  his  head  ache,  is  relieved  by  the 
equal  distribution  of  blood,  and  the  feet  that  were  cold, 
because  of  imperfect  circulation,  become  warm  when  they 
get  their  share  of  blood. 

Fat  is  deposited  in  the  cheek.     How  does  it  get  there  ? 

Answer. — In  two  ways:  First — Starch  is  eaten,  is 
changed  by  saliva  to  sugar  (or  sugar  is  eaten).  It  is 
absorbed  by  the  blood  vessels  of  the  stomach,  carried  to 
the  liver  by  the  portal  vein,  changed  to  glycogen,  carried 
to  heart,  to  lungs,  to  heart  again,  to  artery  of  neck  and 
face,  and  deposited  by  capillaries  in  the  cheek.  Sec- 
ond— Fat  is  eaten,  is  digested  by  bile  and  pancreatic 


236  HYGIENE. 

juice,  absorbed  by  villi,  carried  by  lacteals  to  the  thoracic 
duct,  to  the  left  vein  under  the  clavicle,  then  to  the  heart, 
and  from  the  heart  as  above. 

Name   other   injuries   that   require  proteid  food,  and 
trace  its  way  on  its  journey  to  repair  the  injury. 


MEMORY  QUESTIONS.  237 

MEMORY  QUESTIONS. 


CHAPTER   1. 

What  is  health? 

How  can  people  keep  healthy? 

Why  should  a  person  study  hygiene? 

What  is  disease  ? 

What  causes  catching  diseases  and  others? 

Describe  heredity,  with  illustrations. 

Who  are  the  persons  most  interested  in  hygiene,  and  why? 


CHAPTER  2. 

What  will  keep  bones  healthy? 

Why  are  children's  bones  more  liable  to  injury  than  those  of  older 
persons  ? 

How  are  they  injured? 

Name  seven  ways  of  getting  deformed. 

How  does  standing  crooked  affect  the  ligaments? 

Upon  whom  should  a  person  depend  for  a  straight,  strong  body? 

In  what  two  ways  does  clothing  affect  bones? 

In  what  three  ways  do  tight  and  high-heeled  shoes  injure? 

Why  are  children  often  hungry? 

What  two  substances  are  good  bone  food? 

Why  should  a  broken  limb  not  be  allowed  to  swing? 

What  should  be  done  first  when  a  limb  is  broken? 

What  is  the  difference  between  a  sprain  and  a  broken  bone? 

What  should  be  done  with  a  sprain  ? 

In  what  two  ways  are  colds  often  taken? 

What  part  of  the  bones  is  affected  by  colds  ? 

What  should  be  done  after  a  person  has  been  exposed  to  rain? 


CHAPTER   3. 

What  is  one  of  the  first  laws  of  health? 

Why  must  our  muscles  be  used? 

What  effect  has  exercise  on  the  heart?    On  circulation? 


238  HYGIENE. 

Why  should  not  children  exercise  too  hard? 

Name  six  kinds  of  exercise. 

What  are  the  reasons  that  walking  is  so  good  exercise? 

What  adds  to  the  pleasure  of  walking? 

What  three  effects  has  over  exertion? 

Why  are  athletes  not  often  long  lived? 

What  is  lumbago? 

Name  another  disease  that  comes  from  exposure  to  wet  or  cold. 

Why  is  it  dangerous  to  sit  in  wet  clothing? 

Describe  fatty  degeneration. 

What  would  be  the  effect  if  an  order  to  contract  came  to  a  muscle 
that  was  part  fat? 

Draw  fatty  and  normal  heart  muscle,  so  as  to  show  the  difference 
between  them. 

What  causes  palpitation  of  the  heart? 

Describe  trichina  in  muscle. 

How  can  any  one  avoid  enlargement  or  palpitation  of  the  heart? 


CHAPTER   4. 

Why  should  the  skin  be  kept  clean? 
How  does  it  get  unclean? 

What  is  a  rule  to  follow  as  to  frequency  of  baths  ? 
What  should  be  the  effect  of  a  bath  ? 
Why  is  cold  water  generally  best? 
Why  should  baths  be  frequent  in  California? 
What  are  the  advantages  of  sea  bathing? 
How  are  chapped  hands  caused? 
What  are  cosmetics,  and  why  are  they  used? 
Name  three  ways  in  which  they  injure  the  skin  ? 
What  are  the  poisons  used  ? 
How  can  a  person  get  a  good  complexion  ? 
Why  are  hair  dyes  and  hair  bleaching  injurious? 
Are  there  any  pores  in  the  skin  of  the  scalp? 
How  is  painter's  colic  caused  ? 
Does  lead  injure  in  any  other  way  ? 
Describe  poisoning  by  poison  ivy. 
What  is  the  reason  flannel  makes  good  clothing? 
Why  should  clothing  be  frequently  changed  ? 
Give  three  reasons  why  blankets  make  good  bedding. 
What  conditions  make  it  easy  for  a  person  to  take  cold  ? 


MEMORY  QUESTIONS.  239 

Describe  how  a  cold  affects  various  parts  of  the  mucous  mem- 
brane. 

What  causes  corns  ? 

How  can  a  slight  burn  be  cured? 

How  does  an  extensive  burn  sometimes  affect  the  lungs,  and 
'why? 


CHAPTER   5. 

Elements,  Compounds,  and  their  Action. — Define  food.  Why  do 
we  have  to  understand  the  composition  of  food  ? 

What  is  a  compound?  Define  element,  and  give  example. 
About  how  many  elements  are  there?  How  many  found  in  the 
body?  What  becomes  of  elements  when  compounds  are  destroyed? 
Is  heat  an  element  ?  How  is  it  produced  ? 

What  is  the  difference  between  wood  burned  up  and  wood 
decayed  in  the  forest?  What  is  iron  rust?  How  do  people  keep 
iron  from  rusting?  What  part  of  the  air  rusts  it?  What  makes  a 
fire  burn  brighter?  How  does  a  person  keep  warm  without  a  fire? 
How  does  a  person  starve?  What  becomes  of  the  food  a  person 
eats  after  he  is  full  grown?  Describe  work  power.  What  are  the 
compounds  of  a  body  called?  What  effect  has  oxygen  on  com- 
pounds? What  becomes  of  the  new  compounds  formed?  What 
happens  if  new  material  is  not  supplied  ? 

If  a  person  wants  to  increase  his  muscle,  is  lean  meat  the  only 
thing  to  eat? 

What  happens  to  meat  and  vegetables  that  are  eaten? 

Kinds  and  Classes  of  Food. — Name  the  two  kinds  and  the  classes 
of  foods.  What  is  the  difference  between  organic  and  inorganic 
food? 

Describe  salt  as  a  food.  Where  does  the  lime  for  bones  come 
from  ?  Why  do  people  need  much  water  ? 

What  does  ordinary  drinking  water  contain  ?  What  makes  water 
often  impure?  Why  can  water  look  clean,  and  still  be  harmful? 
If  one  is  suspicious  of  the  water,  what  should  be  done  with  it  ? 

How  do  the  classes  of  organic  foods  differ  in  use?  Name  the 
characteristics  of  proteids.  Name  the  principal  proteids.  Describe 
albumen.  Where  is  fibrin  found?  How  does  fibrin  differ  from 
gluten?  In  what  two  compounds  is  casein  found? 

Where  are  fats  found?    Are  there  any  vegetable  fats? 


240  HYGIENE. 

Name  the  members  of  the  starch  class.  Why  are  they  put 
together?  Are  any  of  the  starch  class  of  animal  origin? 

Why  is  a  mixed  diet  necessary  ?  If  a  mixed  diet  is  taken,  what 
things  are  most  important?  In  eating  oatmeal  and  milk,  which 
furnishes  proteids  and  which  fats?  In  eating  pork  and  beans, 
which  article  gives  starches,  which  proteids,  and  which  fats  ?  T6 
which  class  does  beefsteak  belong?  Potatoes?  Cheese?  Crackers? 
Why  are  oatmeal,  cracked  wheat,  and  graham  bread  good  food? 

Which  are  the  most  nourishing  kinds  of  meat?  What  kinds  of 
meat  are  hardest  to  digest?  Why  is  cheese  hard  to  digest?  What 
is  beef  tea  good  for?  What  are  the  three  common  sources  of  fatty 
foods?  Why  is  a  meat  and  vegetable  diet  generally  better  than 
an  exclusively  vegetable  diet?  What  foods  should  not  be  eaten 
together  ?  What  needs  are  supplied  by  fruits  ? 

What  are  condiments,  and  of  what  use  are  they  ? 

Define  a  stimulant.     Why  should  not  children  use  tea  and  coffee  ? 

Describe  tea ;  describe  coffee.  How  does  strong  tea  affect  people  ? 
What  is  the  name % of  the  stimulant  in  tea,  coffee,  and  chocolate? 
Why  is  chocolate  the  most  nourishing  ? 

Condition  and  Preparation  of  Foods. — Why  should  meats  be  fresh? 
What  is  the  disadvantage  of  salted  and  smoked  meats?  In  how 
many  ways  are  canned  goods  injurious?  What  are  the  advantages 
of  canned  goods  ?  What  is  the  use  of  cooking  food  ?  What  is  the 
best  way  of  cooking  meat,  and  why  ?  What  happens  if  meat  to  be 
boiled  is  put  in  cold  water  ? 

What  is  a  parasite  ?  How  does  it  get  into  food  ?  What  harm  does 
it  do  in  the  system?  Name  two  kinds.  Where  does  each  come 
from  ?  How  can  they  always  be  prevented  ? 

Taste,  Climate. — Give  illustration  of  individual  taste  and  pecul- 
iarity in  food.  What  difference  does  occupation  make?  How 
should  diet  differ  with  the  seasons  ?  How  should  diet  differ  between 
people  of  the  tropics  and  those  of  Arctic  regions  ? 

Digestion. — Where  are  different  classes  of  food  digested?  Why 
should  meals  be  regular?  Define  adulteration,  and  tell  how  it 
harms  food. 

What  led  to  the  classifying  of  foods?  How  was  St.  Martin  con- 
nected with  the  food  question?  Upon  what  does  good  health 
depend? 

Diseases. — What  effect  do  bad  teeth  have?  Why  does  mucous 
membrane  easily  get  out  of  order?  Name  a  common  form  of  stom- 


MEMORY  QUESTIONS.  241 

ach  disease,  and  how  to  avoid  it.  Name  five  other  diseases  of 
alimentary  canal,  and  their  causes.  What  is  the  cause  of  bilious- 
ness? What  is  jaundice?  Describe  fatty  degeneration  of  liver, 
and  its  effect.  Examine  table  of  habits  and  articles  to  avoid,  to 
find  which  you  should  conquer  in  yourself.  What  is  the  reason 
each  should  be  avoided  ? 


CHAPTER   6. 

Define  a  narcotic. 

What  is  the  use  of  stimulants  and  narcotics? 
Why  are  they  dangerous? 
Why  should  a  person  learn  about  them? 
Name  three  dangerous  common  drugs. 
Name  six  characteristics  of  alcohol. 
What  three  uses  has  alcohol? 
Describe  fermentation. 
How  is  vinegar  made? 

Why  does  bread  dough  sometimes  get  sour? 
Is  pure  alcohol  used  as  a  drink? 
How  much  alcohol  in  wines  and  cider? 
What  else  is  found  in  alcoholic  beverages? 
Which  are  most  dangerous  drinks,  and  why? 
Describe  distillation. 

Where  can  you  see  examples  of  condensation? 
What  adds  to  the  deadly  effects  of  alcoholic  drinks? 
What  is  the  effect  of  large  drinks  of  alcoholic  liquor? 
Why  is  alcohol  not  a  food? 
Why  will  it  not  protect  against  cold? 
Is  it  a  protection  against  the  heat  of  hot  climates  ? 
Why  does  it  not  protect  against  disease? 
What  effect  has  alcohol  on  the  general  system? 
Name  three  diseases  it  causes. 
How  does  it  affect  tissues  and  cells  ? 

Describe  its  effects  on  stomach;  liver;  heart;  lungs;  brain. 
Does  it  benefit  any  of  these? 

Does  it  affect  all  tissues  and  organs  of  every  one  who  uses  it? 
Why  is  it  that  some  people  do  not  consider  it  injurious? 
Of  two  people  nearly  alike,  which  will  have  the  better  chance  in 
life,  the  man  who  drinks,  or  the  man  who  does  not,  and  why? 


242  HYGIENE. 

QUESTIONS  ON  NARCOTICS  AND  OTHER  POISONS. 

What  is  opium  made  from? 

Where  is  it  used  most?    How  is  it  used? 

Why  is  there  danger  of  its  being  used  in  California? 

How  does  it  differ,  in  effect,  from  alcohol? 

How  does  it  affect  the  brain  ? 

What  systems  does  it  affect? 

How  does  it  kill  people? 

What  are  other  forms  of  opium  ? 

Which  is  most  dangerous,  and  wrhy? 

What  is  the  harm  of  using  soothing  syrups  to  quiet  fretful  chil- 
dren? 

What  are  bitters ;  quack  medicines ;  and  the  harm  of  using  them  ? 

Why  have  doctors  nearly  given  up  the  use  of  tobacco  as  a  medi- 
cine? 

What  is  the  poison  of  tobacco? 

How  does  it  affect  the  heart? 

What  effect  has  tobacco  on  the  mucous  membrane  and  organs 
contained  by  it? 

How  does  it  affect  the  glands,  and  what  is  the  harm  done? 

What  effect  has  it  on  growing  boys,  and  why? 

Define  a  poison;  an  antidote. 

How  can  a  child  get  poisoned  ? 

What  is  a  common  antidote,  and  how  does  it  act? 

What  should  be  done  for  a  child  who  has  taken  laudanum  ? 

Why  not  use  an  emetic  when  any  one  has  taken  oxalic  acid? 

What  will  be  good  to  take  ? 

How  does  egg  act  on  blue  vitriol? 


CHAPTER   7. 

What  generally  causes  diseases  of  the  circulatory  organs? 
How  does  the  blood  get  out  of  order? 
Where  must  it  be  doctored? 
What  parts  of  the  heart  are  often  affected? 
What  is  the  use  of  valves  to  a  heart? 
What  happens  if  the  valves  get  thick?    Get  thin  ? 
Describe  the  result  if  the  valve  between  the  left  auricle  and  ven- 
tricle should  get  too  small. 
Define  dropsy. 


MEMORY  QUESTIONS.  243 

What  causes  disease  of  valves? 

What  effect  has  inflammation  of  serous  membrane  of  heart? 
Why  do  people  faint? 

How  can  any  one  tell  when  an  artery  is  cut? 
Why  is  cold  water  sometimes  put  on  the  surface  near  a  wound? 
Why  not  put  it  right  on  the  wound? 
What  is  the  use  of  pressure  ? 

How  can  ordinary  nosebleed  be  checked,  and  why? 
Why  should  wounds  be  covered? 
Why  is  it  dangerous  to  cut  corns? 
What  is  the  cause  of  cold  feet? 
How  can  cold  feet  be  prevented? 
What  is  congestion? 
Why  are  kidneys  liable  to  disease? 
What  causes  such  disease? 

Examine  table  "  Things  to  Avoid,"  and  tell  why  each  thing 
should  be  avoided. 


CHAPTER  8. 

How  much  of  the  air  is  oxygen? 
What  part  of  the  blood  carries  it? 
Why  do  tissues  need  it? 

Where  is  heat  produced?    What  is  body  temperature? 
Why  are  people  uncomfortable  when  the  weather  is  99°? 
How  does  the  heat  of  the  body  get  equalized? 
Describe  carbon  .dioxide. 

Where  does  it  come  from,  and  what  becomes  of  it? 
What  is  the  most  harmful  part  of  expired  air? 
What  is  the  effect  of  breathing  bad  air? 
Define  ventilation. 
What  is  the  difficulty  about  it? 
How  can  a  school  room  be  ventilated? 
What  two  things  are  good  for  ventilating  rooms? 
Can  cool  air  ever  be  impure  ? 
Give  an  example  of  warmed  pure  air. 
What  is  it  in  the  air  that  makes  it  good? 
How  can  any  one  tell  if  air  in  a  room  is  bad? 
Give  two  illustrations  of  sudden  death  from  want  of  ventilation. 
What  is  the  harm  of  compressing  the  chest? 
What  organs  are  affected? 
16— P 


244  HYGIENE. 

Will  tight  lacing  lessen  fat? 
What  does  it  do  to  it? 
How  does  lacing  produce  lung  disease? 
What  other  diseases  are  increased  by  it? 
What  effect  has  pressure  on  the  pneumo-gastric  nerve  ? 
Why  is  it  dangerous  to  strike  a  person  in  the  stomach? 
Why  are  the  breathing  organs  liable  to  disease? 
What  effect  has  tobacco? 
Why  are  cigarettes  most  harmful? 
How  does  alcohol  affect  lungs  and  air  tubes? 
What  effect  has  exposure  to  cold  and  wet? 
How  many  kinds  of  bad  air  can  you  name? 
Describe  germs,  or  poisons,  in  air. 

Why  does  one  person  catch  contagious  diseases  and  another 
escape? 

Why  should  bedding,  etc.,  from  a  sick  room,  be  burned? 
What  are  disinfectants,  and  why  are  they  used? 
What  means  should  every  one  take  to  prevent  germ  diseases? 
Name  five  diseases  of  breathing  organs. 


CHAPTER  9. 

Why  are  the  senses  of  savages  more  acute  than  ours? 

What  is  meant  by  toleration? 

What  affects  special  senses? 

What  would  a  disease  that  destroys  the  sense  of  touch  be  called? 

What  will  keep  taste,  touch,  and  smell  in  good  working  order? 

How  can  the  hearing  be  injured? 

Why  should  a  person  not  doctor  his  own  eyes? 

How  does  stooping  over  injure  the  eyes? 

Why  should  not  a  person  read  on  the  cars? 

Examine  the  table,  and  tell  why  each  habit  should  be  avoided. 


CHAPTER  10. 

What  does  the  brain  need? 

Why  does  the  brain  need  so  much? 

What  follows  from  the  brain  being  material  ? 

Does  food  ever  stimulate? 

Is  it  necessary  to  eat  brain  food? 


MEMORY  QUESTIONS.  245 

How  does  alcohol  act  on  the  brain? 

What  is  peculiar  about  the  ideas  of  a  person  drunk  on  opium  ? 

Can  a  person  easily  break  the  habit  of  taking  stimulants  and 
narcotics? 

Can  any  one  increase  his  brain  power? 

flow  does  overwork  affect  the  brain? 

Can  any  one  get  rest  by  changing  from  one  exhaustive  labor  to 
another? 

What  is  the  commonest  cause  of  children  and  young  people  break- 
ing down? 

How  should  a  person  study? 

How  long  ought  you  to  study  with  concentration? 

What  effect  has  sleep  on  the  systems  ? 

How  should  a  person  feel  when  he  wakes  up? 

How  can  ordinary  sleeplessness  be  avoided? 

What  often  causes  bad  dreams? 

Why  should  children  sleep  long  hours? 

What  can  keep  children  from  getting  "  nervous?  " 

What  is  a  habit? 

How  are  habits  of  sitting,  eating,  walking,  formed? 

How  can  one  form  habits  of  thought? 

What  is  the  use  of  self-control? 

What  does  it  mean? 

What  is  the  reason  anger  should  be  avoided? 

Why  should  children  be  taught? 

Why  should  they  not  be  allowed  stimulants  and  exciting  amuse- 
ments? 

Why  does  a  child  of  ten  not  know  as  much  as  his  parents  ? 

Why  does  he  think  he  knows  more? 


246  GLOSSARY. 

GLOSSARY. 


Abdomen. — The  lower  part  of  the  trunk  between  the  pelvis  and 

the  diaphragm. 

Accommodation. — The  adjusting  of  parts  of  the  eyeball,  so  that  a 
clear  image  is  formed  on  the  retina.  This  is  done  by  the 
contracting  or  expanding  of  the  iris  and  by  changing  the  liga- 
ment attached  to  the  crystalline  lens.  The  lens  is  flexible  and 
the  ciliary  muscle  either  contracts  or  relaxes,  and  causes  the 
ligament  to  change  the  shape  of  the  lens.  The  lens  modifies 
the  light  entering  the  eye. 
Acetab'ulum. — The  hollow,  or  socket,  of  the  hip  bone  in  which  the 

head  of  the  thigh  bone  fits. 

Acids. — Substance  generally  sour.  They  may  be  of  vegetable,  min- 
eral, or  animal  origin. 

Acetic  Acid. — The  acid  in  vinegar  formed  from  a  kind  of  fer- 
mentation. 

Malic  Acid. — Acid  of  sour  apples. 

Citric  Acid. — The  acid  from  lemons  and  limes. 

These  three  are  vegetable  acids. 

Hydrochloric  or  Muriatic  is  a  mineral  acid,  and  is  made  of 
hydrogen  and  chlorine;  and  sulphuric  acid,  made  of  sulphur, 
hydrogen,  and  oxygen,  is  another. 

Butyric  acid  obtained  from  butter,  palmitic  from  palm  oil, 
and  stearic  from  stearine,  a  kind  of  hard  fat,  are  examples  of 
animal  acids.  These  are  called  fatty  acids  and  are  not  sour. 
Action  of  the  Heart. — The  heart  alternately  contracts  and  relaxes. 
Both  auricles  contract  at  the  same  time  and  then  relax,  then 
almost  immediately  the  ventricles  do  the  same.  The  contrac- 
tion is  called  systole  and  the  dilation  diastole,  and  they  cause 
the  beating  of  the  heart.  The  auricles  have  to  drive  the  blood 
only  a  short  distance  and  have  their  walls  quite  thin,  but  the 
ventricles  have  more  work  to  do,  and  their  walls  are  thicker 
and  stronger.  The  relaxation,  or  diastole,  when  the  auricles 
are  filling,  allows  time  for  a  pause,  and  the  pauses  are  the  rest 
times  of  the  heart  muscle  Altogether  the  pauses  amount  to 
about  nine  hours  a  day. 

Adam's  Apple. — The  projection  in  the  front  of  the  larynx,  most 
strongly  marked  in  men.  It  is  so  called  because  of  the  fancy 
that  the  tempting  apple  of  Eden  stuck  in  Adam's  throat. 


GLOSSARY.  247 

Ad'ipocere. — A  soft,  brownish,  waxy  substance,  into  which  the  fat 
and  muscles  of  animals  are  changed  by  immersion  in  water 
or  alcoholic  liquors,  and  sometimes  by  burial  in  damp  places, 
under  some  unknown  circumstances. 

Adipose  (Fat). — A  tissue  made  of  rounded  masses  of  fat  bound 
together  by  connective  tissue. 

Air. — A  mixture  of  gases  that  surrounds  the  earth.  It  is  made  of 
oxygen,  nitrogen,  carbon  dioxide  (carbonic  acid  gas),  and 
water  vapor.  Often  there  are  particles  of  dust  and  organic 
germs. 

Albino. — A  person,  or  lower  animal,  with  white  skin  and  hair,  and 
no  pigment  to  the  iris,  so  that  the  eyes  look  pink  from  the 
blood  vessels  showing. 

Albu  men. — A  thick,  sticky  substance  found  in  vegetables  and  in 
animal  solids  and  fluids.  It  is  nearly  pure  in  white  of  egg. 

Albuminoid. — Resembling  albumen.  A  group  of  substances  some- 
what like  albumen  in  composition  and  characteristics. 

Alcohol. — A  fine  black  powder  used  for  painting  the  eyebrows ;  after- 
wards used  for  fine  distilled  spirits. 

A  white  liquid  obtained  from  fermentation  of    liquids  and 
distillation  of  their  product.     It  is  present  in  all  liquors. 

Aliment. — Food,  nourishment,  that  which  supplies  material  for 
natural  growth. 

Alimentary  Canal. — The  long  twisted  tube  that  extends  from  lips  to 
anus,  by  which  the  food  is  ground  up,  digested,  absorbed,  and 
the  waste  portion  expelled.  It  includes  mouth,  larynx,  gullet, 
stomach,  small  and  large  intestines. 

Alkali. — A  substance,  like  soda  or  potash,  that  is  caustic,  or  burn- 
ing, and  unites  with  fats  to  make  soaps. 

Alkaline. — Substances  that  act  somewhat  like  soda  or  potash.  Lime 
does  this,  and  water  with  too  much  lime  is  sometimes  called 
alkaline. 

Alve'olus  (plural,  alveoli). — The  hollow,  or  cavity,  in  the  jaw  in 
which  are  set  the  teeth  (teeth  sockets). 

Amyloids. — A  group  of  foods,  the  starches,  which  includes  gum, 
starch,  and  sugar. 

Annular  Ligament. — A  band  of  ligament  to  keep  tendons  in  place, 
as  at  the  wrist  and  ankle. 

Aor'ta. — The  great  trunk  of  the  arteries,  which  goes  from  left  ven- 
tricle. It  is  divided  into  ascending  portion,  the  arch  (a  part 
which  curves  backward),  and  a  descending  portion;  and  it 
gives  off  branches  to  all  parts  of  the  body. 


248  GLOSSARY. 

Appendages. — Of  ear :  All  parts  except  tue  inner  ear,  which  is  called 
the  essential  part.  Of  eye :  All  parts  except  the  eyeball,  which 
is  the  essential  organ  of  sight.  Of  skin :  Hair,  nails,  and  teeth, 
oil  and  sweat  glands,  and  their  ducts. 

Appetite. — A  desire  for  food  due  to  the  condition  of  the  mucous 
membrane  of  the  stomach  when  food  is  needed  by  the  tissues. 

Ar'bor  Vi'tse. — The  tree-like  arrangement  of  gray  matter  and  white 
matter  seen  in  a  section  of  the  cerebellum. 

Are'olar  Tissue. — A  loose  kind  of  connective  tissue  containing  many 
spaces  or  cells.  Sometimes  it  is  called  cellular  tissue,  and  it  is 
found  between  skin  and  muscles. 

Artery. — A  blood  vessel  to  carry  blood  from  the  heart.  Arteries 
remain  open  after  death,  and  the  ancients  thought  they  were 
air  tubes. 

Articulations  (Joints). — The  places  where  two  or  more  bones  are 
formed. 

Asphyxia. — A  suspension  of  respiration  from  drowning,  or  from 
exposure  to  suffocating  gases. 

Assimilation. — The  making  alike.  As  the  tissues  wear  out  they  take 
from  the  blood  liquid  food,  something  unlike  them,  but  having 
the  same  elements,  and  of  this  they  make  their  own  particular 
kind  of  tissue. 

Astig'matism. — A  trouble  of  the  eyes  where  a  blurred  image  is  made 
on  the  retina,  because  of  irregular  refraction  of  light. 

Banting. — Bantingism.  A  method  of  reducing  undue  corpulence  by 
abstaining  from  fatty,  starchy,  or  sugary  food.  Called  so  from 
William  Banting,  of  London. 

Biceps. — A  muscle  in  the  front  of  the  arm  that  has  its  origin  from 
the  shoulder  joint  by  two  heads. 

Bicuspid. — A  tooth  with  two  points. 

A  valve  of  the  heart,  between  left  auricle  and  ventricle,  hav- 
ing two  flaps  of  membrane.     (Mitral  valve.) 

Bilateral  Symmetry. — A  shapeliness  caused  by  two  sides  being  equal 
and  alike,  as  the  sides  of  the  human  body. 

Bile  (Gall). — A  golden  brown,  bitter,  sticky  fluid  secreted  by  liver, 
and  stored  in  bile  bladder.  Considered  a  secretion  and  an 
excretion. 

Bladder. — A  sac  in  animals  used  for  holding  liquids,  as  the  bile 
bladder,  or  cyst,  for  holding  gall  or  bile,  and  the  urinary  blad- 
der, connected  with  the  kidneys,  for  holding  urine. 


GLOSSARY.  249 

Blushing. —To  grow  red  and  warm.  Caused  by  some  mental  or 
nerve  stimulus  which  checks  the  action  of  smaller  nerves  of 
capillaries,  and  then  the  blood  fills  these  vessels  on  the  sur- 
face, giving  rise  to  warmth  and  color. 

Bone. — The  hard  white  substance  which  supports  the  body.  It  is 
composed  of  mineral  and  animal  matter.  The  mineral  is  cal- 
cium carbonate,  phosphate  and  fluoride,  sodium  chloride,  and 
magnesium  phosphate.  The  bone  tissue  is  arranged  around 
microscopic  canals,  called  Haversian  (Havers,  proper  name) 
canals,  which  branch  in  all  directions  through  the  bone.  From 
these  canals  little  wavy  tubes,  called  canaliculi,  extend  and 
connect  them  with  elliptical  hollows,  called  lacunx. 

Bronchus  (plural,  bronchi}. — A  branch  of  the  windpipe.  There  are 
two.  One  branch  enters  the  right  lung  and  the  other  the  left 
lung.  They  subdivide  again  and  again,  forming  the  bronchial 
tubes,  which  end  in  the  air  sacs. 

Bunion. — An  enlargement  of  a  small  membranous  sac  (bursa),  usu- 
ally on  the  inside  of  the  first  joint  of  the  large  toe. 

Burns. — Injuries  by  fire.  If  they  are  slight,  no  serious  results  follow ; 
but  if  much  of  the  surface  is  injured  congestion  of  the  lungs 
may  set  in,  because  so  much  extra  work  is  thrown  on  the  lungs 
by  the  destruction  of  exhaling  organs  of  the  skin. 

Bur'sae  Mueo'sse. — Small  sacs  full  of  sticky  liquid  situated  under  the 
tendons  at  the  joints.  Bursa}  can  be  seen  by  pressing  the  thick 
part  of  the  palm  of  the  hand  near  the  wrist. 

Caecum. — The  beginning  of  the  large  intestine. 

Caff'ein. — A  brittle,  white  substance  obtained  from  coffee.  It  is  the 
stimulating  principle,  and  is  also  found  in  tea,  Paraguay  tea, 
and  chocolate.  Theine  is  a  name  that  was  given  to  the  tea 
principle  before  it  was  learned  that  it  is  identical  with  caffein. 

Canal. — Alimentary  (p.  247). 

Auditory. — The  bony  tube  of  the  outer  ear  that  extends  from 
the  cartilage  part,  pinna,  to  the  membrane  of  the  tympanum. 
This  canal  is  almost  an  inch  long  and  a  quarter  of  an  inch  wide. 
Lachrymal. — Two  small  canals  on  the  inner  side  of  the  eyes 
connecting  small  openings  on  the  lids  with  the  nasal  duct,  to 
carry  off  tears. 

Semicircular  Canals  of  the  Ear. — Three  canals  in  internal  ear 
said  to  have  something  to  do  with  equilibrium  of  body,  for 
when  they  are  destroyed  the  balance  of  the  body  is  lost.  Their 
best  known  function  is  connected  with  hearing. 


250  GLOSSARY. 

Spinal. — The  hollows  in  the  vertebras  through  which  the 
spinal  cord  passes. 

Canaliculi. — The  small,  wavy  tubes  in  the  bones  that  connect  the 
Haversian  canals  with  the  lacunae. 

Carbohydrates. — A  group  of  substances  composed  of  carbon,  hydro- 
gen, and  oxygen,  in  which  hydrogen  and  oxygen  are  in  the 
same  proportions  as  in  water.  These  substances  are  cellulose, 
opium,  starch,  and  sugar.  The  amyloids  or  starches. 

Carbon. — An  element  that  occurs  in  three  forms,  as  coal,  as  diamond, 
and  as  graphite,  or  so  called  black  lead. 

Ca'seine  (written  also  Casein). — A  nitrogenous  substance  found  in 
plants  and  animals.  In  milk  it  is  the  part  that  curdles  and 
forms  the  curd  for  making  cheese ;  in  vegetables  it  is  found  in 
leguminous  plants,  as  pease  and  beans,  and  is  sometimes  called 
legumine. 

Cat'alepsy. — A  sudden  suspension  of  volition  and  sensation. 

Cauda  equina  (Horse' s  tail). — A  name  given  to  the  mass  of  nerves 
that  extends  from  the  end  of  the  spinal  cord  at  the  second 
lumbar  vertebra  through  and  to  the  end  of  the  spinal  canal. 

Cellulose. — The  vegetable  fibre  that  forms  the  walls  of  cells.  It  can 
be  changed  into  starch  and  sugar.  In  the  food  canal  it  is  use- 
ful in  keeping  the  mass  of  food  distended  so  that  the  digestive 
juices  can  penetrate  and  surround  the  food  particles. 

Cer'ebro- Spinal  System. — The  part  of  the  nervous  system  that  is 
composed  of  brain,  spinal  cord,  cranial  and  spinal  nerves. 

Ceru'men  (Ear  wax). — A  kind  of  bitter,  yellow,  thick  oil  secreted 
from  glands  in  the  ear  that  are  something  like  the  oil  glands 
of  the  rest  of  the  skin. 

Chloral. — A  liquid  made  by  the  action  of  a  gas  called  chlorine  on 
alcohol  in  sunlight.  It  produces  sleep.  It  is  a  dangerous  drug 
that  enslaves  something  as  alcohol  and  opium  do,  by  com- 
pelling increase  of  dose  till  a  person  has  formed  the  "chloral 
habit."  This  habit  deranges  the  organs  of  the  body  and  weak- 
ens the  mind. 

Chloroform. — An  oily  liquid  used  to  lessen  pain  and  produce  insen- 
sibility during  surgical  operations.  It  is  volatile  and  has  a 
pungent  odor.  It  is  a  dangerous  drug  and  should  never  be 
used  unless  by  a  physician's  order. 

Ciliary  Muscles  and  Processes.— The  muscles  are  connected  with  the 
choroid  coat  and  help  in  accommodation.  The  processes  are  a 
number  of  folds  of  the  choroid  coat  radiating  backward  from 
the  junction  of  the  cornea  and  choroid, 


GLOSSARY.  251 

Coats  of  Brain.— The  membranes  that  cover  the  brain  are  three  in 
number.  Next  to  the  bone  the  membrane  of  connective  tissue 
is  a  kind  of  periosteum  which  nourishes  the  bone  and  lines  the 
cranial  cavity,  and  it  is  called  dura  mater.  The  second  coat, 
called  arachnoid,  is  in  two  layers,  and  between  these  layers 
there  is  a  liquid.  The  third  membrane,  called  pia  mater,  is  next 
to  the  brain  and  nourishes  it. 

Cocaine. — A  preparation  from  a  South  American  plant  (cocoa)  which 
produces  insensibility  to  pain  when  applied  to  the  surface  of  the 
body.  It  is  used  by  dentists  as  a  local  pain  killer. 

Coccyx. — The  end  of  the  spinal  column,  formed  of  a  few  small 
imperfect  vertebrae,  and  supposed  to  look  like  a  cuckoo's  bill. 

Color  Blindness  (Daltonism}. — An  imperfection  of  eyesight  which 
makes  it  impossible  for  the  person  afflicted  to  tell  the  difference 
between  certain  colors.  Generally  the  colors  are  red  and  green, 
the  person  not  being  able  to  tell  ripe  cherries  from  the  leaves 
except  by  shape.  Another  form  is  inability  to  tell  the  differ- 
ence between  green  and  blue.  It  is  called  Daltonism  from  John 
Dalton,  who  first  made  the  disease  known,  his  own  eyes  being 
.  so  affected.  Much  of  the  so  called  color  blindness  is,  however, 
mere  color  ignorance. 

Colum'nse  Carnese. — The  fleshy  columns  of  the  heart  to  which  are 
attached  the  chordee  tendin'e&,  or  tendon  cords,  which  keep 
the  flaps  of  the  ventral  and  tricuspid  valves  from  pushing 
through  the  openings  when  the  ventricles  contract. 

Conjunctiva. — The  mucous  membrane  that  covers  the  front  part  of 
the  eyeball  and  the  inner  surface  of  the  eyelids. 

Constipation. — An  overfull  condition  of  the  large  intestine,  caused 
generally  by  want  of  regular  exercise,  proper  diet,  and  care- 
lessness about  regular  daily  evacuation  of  contents  of  bowels. 
The  accumulation  of  waste  material  causes  disease.  Regu- 
larity in  getting  rid  of  egesta  is  one  of  the  most  important 
habits  for  preserving  health. 

Corpus  Callo'sum. — A  band  of  white  nerve  matter  that  binds  together 
the  hemispheres  of  the  cerebrum. 

Corpus'cles. — Small  bodies.  Those  of  taste  and  touch  are  made  of 
nerve  material. 

Delirium  Tremens. — A  disease  produced  by  long  or  excessive  use  of 
alcoholic  liquors.  Connected  with  physical  disorder  and  weak- 
ness are  strange  delusions.  The  person  imagines  he  is  perse- 
cuted, is  surrounded  by  horrible  creatures,  and  his  sight  and 
hearing  give  him  distorted  and  unnatural  impressions  of  objects. 


252  GLOSSARY. 

Digestibility  of  Foods.— The  ability  of  foods  to  be  worked  over  into 
-  a  substance  of  which  to  make  tissues  dependent  upon  their 
hardness,  structure,  and  the  manner  they  are  prepared.  All 
nutritive  articles  are  not  easily  digested,  therefore  the  value  of 
food  depends  as  much  on  digestibility  as  on  nutritive  quality. 
Cheese  is  nutritive,  but  not  easily  digested. 

Dipsomania. — An  uncontrollable  thirst  for  alcoholic  liquors.  A  form 
of  insanity  produced  by  indulgence  in  liquor,  or  oftener  by 
inheritance  from  parents  addicted  to  alcoholic  liquors. 

Drainage. — Carrying  off  waste  water.  The  ground  around  a  dwell- 
ing house  should  be  well  drained,  and  the  drainage  should  be 
so  directed  that  the  waste  water  cannot  pollute  the  wells  or 
springs.  Carelessness  about  drainage  is  the  source  of  sickness. 

Dreams. — The  thoughts  of  a  person  asleep.  The  action  of  thought 
centers  when  not  under  control  of  the  will. 

Duode'num. — The  first  part  of  small  intestine,  so  called  because  its 
length  is  about  twelve  fingers'  breadth. 

Eges'ta. — The  solid  part  that  remains  after  food  is  digested  and  which 
leaves  the  body  by  the  rectum.  It  consists  of  the  cellulose  of 
vegetables,  pits  and  skins  of  fruit,  and  waste  nitrogenous  matter. 

Elbow  Joint. — This  joint  is  made  by  the  articulation  of  the  humerus, 
with  the  radius,  and  the  ulna.  The  head  of  the  radius  rolls 
around  the  ulna,  so  that  the  radius  crosses  over  the  ulna.  This 
gives  extra  freedom  to  the  hand.  Extend  the  hand  palm  up- 
ward. By  motion  of  the  forearm  turn  the  palm  down,  and 
the  rolling  action  of  the  radius  will  be  understood.  The  end 
of  the  ulna  extends  beyond  the  joint,  forming  a  process  called 
"funny  bone,"  or  olecranon  process. 

Elements. — The  elements  of  the  body  are  fourteen  in  number:  Oxy- 
gen, hydrogen,  nitrogen,  carbon,  sulphur,  phosphorus,  fluorine, 
chlorine,  sodium,  potassium,  calcium,  magnesium,  silicon,  iron. 

Emotion. — An  agitation  or  stirring  of  the  mind  or  soul.  An  impulse 
of  gray  nerve  matter  that  does  not  produce  muscular  action. 
Examples  of  emotion  are  fear,  anger,  terror,  pity,  revenge, 
love,  hate. 

Emulsion. — A  milky  looking  liquid  formed  by  breaking  up  oil  in 
minute  particles,  the  substance  changing  it  being  often  an 
alkali.  The  fatty  foods  are  made  into  an  emulsion  by  the  alka- 
line pancreatic  juice  before  they  are  absorbed  by  the  villi. 

En'dolymph. — The  fluid  contained  in  the  membranous  bags,  or  laby- 
rinth, of  the  internal  ear.  That  which  surrounds  the  bags  is 
called  perilymph, 


GLOSSARY.  253 

Ethmoid. — A  bone  of  the  skull.  It  forms  the  top  of  the  nasal  cavity 
and  contains  sieve-like  openings,  through  which  branches  of 
olfactory  nerves  pass.  It  also  forms  part  of  the  walls  of  the 
orbital  cavity. 

Eusta'shian  Tube. — The  tube  that  connects  the  throat  and  middle 
ear,  and  serves  as  a  passage  for  air  to  regulate  sound. 

Excretory  Organs. — The  skin,  lungs,  and  kidneys  are  organs  of  excre- 
tion. They  take  from  the  blood  gas,  liquid,  and  solid  waste 
material  in  suspension.  The  skin  excretes  water,  the  lungs 
carbon  dioxide  and  water,  and  the  kidneys  water  and  urea. 

Fats. — A  class  of  foods  called  hydrocarbons,  which  contains  carbon, 
hydrogen,  and  oxygen.  It  includes  fat  meat,  animal  oils,  and 
oils  of  nuts  and  seeds.  The  fats  contain  the  same  elements  as 
the  starches,  but  not  as  much  oxygen,  so  they  unite  in'the  body 
more  readily  with  oxygen,  and  thus  give  more  energy  than 
starches. 

Fenes'tra. — A  small  opening  or  window.  The  oval  (ovalis)  window, 
or  fenestra,  and  the  round  (rotunda)  window,  are  openings 
in  the  bone  between  labyrinth  and  middle  ear.  They  are  closed 
with  membrane. 

Ferments. — A  class  of  nitrogenous  substances  that  cause  fermenta- 
tion. Each  digestive  juice  has  a  ferment,  that  of  saliva  being 
ptyalin;  of  gastric  juice  being  pepsin;  of  bile  and  pancreatic 
juice,  pancreatin,  or  trypsin;  of  intestinal  juices,  unknown. 

Fibula. — The  small  bone  of  the  leg.  The  large  one  is  called  tibia, 
or  shin  bone. 

Fi'brin. — The  net  work  of  elastic  albuminous  fibres  that  draws  all  the 
solid  parts  of  blood  together  in  forming  a  clot  is  called  fibrin. 
Vegetable  fibrin,  called  gluten,  is  in  tough,  whitish  masses. 
The  albuminous  matter  of  muscle  is  sometimes  called  muscle 
fibrin,  but  more  properly  is  myosin. 

Follicle. — A  follicle  is  a  little  pouch  or  pocket.  The  follicles  of  the 
hair  are  depressions  of  the  cuticle.  In  the  small  intestine  there 
are  a  number  of  pouches  connected  with  the  formation  of  intes- 
tinal digestive  juice,  which  are  called  follicles  of  Lieberkiihn. 

Fora'men  (plural,  foram'ina). — An  opening.  Generally  it  is  a  small 
opening,  but  it  is  large  in  the  foramen  magnum,  the  opening 
in  the  base  of  the  skull,  the  passage  for  the  spinal  cord.  The 
fenestra  ovalis  and  fenestra  rotundum  of  the  ear  are  foramina. 
Numerous  foramina  can  be  found  at  the  base  of  the  skull,  and 
in  the  long  bones,  where  they  serve  for  entrance  and  exit,  of 
nerves  and  blood  vessels. 


254  GLOSSARY. 

Ganglion  (plural,  ganglia). — A  mass  of  nerve  matter  consisting  of  a 
number  of  nerve  cells  and  radiating  fibres.  There  are  ganglia 
connected  with  the  brain,  spinal  cord,  and  sympathetic  sys- 
tem, and  they  vary  in  size  from  microscopic  dimensions  to 
about  an  inch  long. 

Glands. — Glands  are  organs  that  either  form  a  new  fluid  from  the 
blood  for  the  use  of  the  body,  or  modify  the  blood  as  it  passes 
through  them.  They  vary  in  size,  and  attend  to  secretion  and 
excretion.  They  are  divided  into  two  classes :  those  with  ducts, 
and  those  without  them.  The  ductless  glands  are :  the  lacteals 
(mesenteric)  of  the  intestines,  the  lymphatics  of  the  lymphatic 
system,  the  spleen  and  thyroid  and  thymus  glands  of  the  neck 
(function  unknown),  and  the  supra  renal  capsules  (function 
unknown).  The  glands  with  ducts  are:  the  gastric  of  the 
stomach,  the  intestinal  (glands  of  Brunner,  and  follicles,  or 
crypts  of  Lieberkiihn)  of  the  intestines,  the  kidneys,  the  lach- 
rymal of  the  eye,  the  liver,  the  mucous  of  the  mucous  mem- 
brane, the  oil  (or  sebaceous)  of  the  skin,  the  pancreas,  the 
perspiratory  (sweat,  or  sudoriparous)  of  the  skin,  and  the  sali- 
vary (parotid  sublingual,  submaxillary)  of  the  mouth. 

Glucose. — A  kind  of  sugar  obtained  from  most  fruits,  and  also  formed 
by  action  of  sulphuric  acid  on  starch,  or  cellulose.  It  is  not  as 
sweet  as  cane  sugar.  It  is  also  called  grape  sugar,  or  starch 
sugar.  Saliva  changes  insoluble  starch  into  soluble  sugar. 

Glycerine. — A  sweet,  sticky,  yellowish  liquid,  obtained  from  fatty 
substances  in  soap  making.  Its  stickiness  makes  it  useful  for 
putting  on  chapped  skin  to  keep  the  air  away. 

Gly'cogen. — An  animal  starch.  It  is  a  white  powder  when  pure.  It 
is  made  by  the  liver  from  the  proteid  and  starch  foods,  stored 
in  liver  cells,  and  given  out  as  sugar  when  needed  by  the  body. 

Hsem'oglobin. — The  larger,  solid  part  of  the  colored  corpuscles  of  the 
blood  is  called  haemoglobin.  It  is  composed  of  carbon,  hydro- 
gen, oxygen,  nitrogen,  sulphur,  and  iron.  It  contains  much 
iron.  It  has  a  great  affinity  for  oxygen,  and  when  the  corpus- 
cles contain  a  quantity  of  this  gas,  and  the  blood  is  red,  the 
haemoglobin  becomes  oxy-hsemoglobin. 

Hasn'eesh. — Indian  hemp.  A  narcotic  that  is  used  in  the  East  to 
produce  sleep — insensibility  to  pain.  It  sometimes  causes  con- 
vulsions. 

Hyoid  Bone. — A  small  U-shaped  bone  at  the  base  of  the  tongue  for 
the  attachment  of  muscles. 


GLOSSARY.  255 

Indigestible  Substances. — Indigestible  material  is  that  which  either 
from  its  structure  or  preparation  cannot  be  acted  on  by  the 
digestive  juices.  Husks  and  seeds  of  vegetables,  some  of  the 
tissues  that  bind  meats  together,  and  badly  cooked  food,  are  of 
this  class.  With  various  excretions  they  form  what  is  called 
egesta,  and  pass  from  the  body  by  the  way  of  the  large  intestine. 

Indigestion. — Inability  to  digest  food.  This  causes  various  forms  of 
dyspepsia,  which  may  be  accompanied  with  loss  of  appetite,  by 
pain  on  eating,  or  merely  by  general  uncomfortableness.  Indi- 
gestion may  be  due  to  natural  weakness  of  the  digestive  organs, 
but  is  generally  caused  by  bad  habits  of  eating. 

Inorganic  Foods. — Inorganic  foods  are  derived  from  the  mineral  king- 
dom, and  are  generally  simpler  than  the  organic  foods.  They 
are  compounds  of  lime,  iron,  magnesium,  carbon,  oxygen, 
nitrogen,  sulphur,  fluorine,  chlorine,  and  phosphorus,  and  are 
taken  in  the  body  as  water  or  as  part  of  organic  food. 

Insalivation. — Moistening  the  food  with  saliva.  This  commences 
the  digestion  of  starch  food,  and  also  softens  the  mass  so  that 
it  can  be  easily  swallowed. 

Intercostal  Muscles. — Muscles  between  the  ribs,  which  aid  in  respi- 
ration. 

Intestines. — The  smaller  is  in  three  parts:  duodenum,  ileum,  jeju- 
num ;  and  the  larger  consists  of  caecum,  colon,  rectum. 

Iris. — Muscular  disc  in  front  of  the  crystalline  lens.  It  has  fibres 
running  around  the  disc  and  others  radiating  from  the  pupil 
to  the  edge  of  the  disc.  The  iris  gives  color  to  the  eye,  and 
is  an  appendage  to  the  choroid  coat. 

Koumiss  (kumiss). — A  fermented  intoxicating  drink  made  from 
mare's  milk  originally  by  the  Calmucks. 

Lactose. — Milk  sugar;  an  animal  sugar  found  in  milk. 

Legu'min. — A  kind  of  vegetable  caseine  that  is  found  in  pease  and 
beans. 

Legu'minous. — Relating  to  plants  that  have  pods,  legumes,  like  pease 
and  beans.  The  order  of  such  plants  is  Papilionacex. 

Lens.— A  glass  that  changes  the  direction  of  light.  The  crystalline 
lens  acts  on  light  in  the  same  way  as  a  glass  lens  of  the  same 
shape. 

Lu'nula. — The  small  half-moon  places  at  the  bases  of  the  nails. 
They  are  white  because  of  scarcity  of  papillae. 

Lymph. — The  liquid  in  the  lymphatics.  Also  the  liquid  (of  another 
kind)  that  is  inside  (endolymph)  and  outside  (exolymph)  of 
the  membrane  sacs  of  the  inner  ear. 


256  GLOSSARY. 

Marrow. — There  are  two  kinds  of  marrow,  the  red  and  the  yellow. 
The  red,  less  in  quantity,  is  found  in  the  small  space  of  the 
spongy  part  of  bones.  The  yellow,  much  more  in  quantity,  Is 
found  in  the  hollow  shafts  of  the  bones. 

Massage. — A  pressing,  or  kneading,  of  the  muscles  in  order  to 
develop  them.  A  kind  of  treatment  that  serves  somewhat  in 
the  place  of  exercise  for  invalids.  Sometimes  called  "  Swedish 
movement  cure." 

Mastoid  Process. — A  large  process  just  back  of  the  ear,  for  the 
attachment  of  the  sterno-cleido-mastoid  muscle.  * 

Medulla  Oblonga'ta. — The  largest  part  of  the  spinal  cord.  It  is 
inside  the  brain  box,  and  from  it  are  given  off  most  of  the 
cranial  nerves. 

Meibomian. — The  oil  glands  along  the  edge  of  the  eyelids.  Their 
secretion  keeps  the  lids  and  lashes  soft. 

Mesentery. — The  serous  membrane  that  surrounds  and  holds  the 
intestines  in  place.  It  contains  many  small  glands  connected 
with  the  digestive  system  that  are  called  lacteal  or  mesenteric 
glands. 

Mouth  and  Pharynx  Absorption. — Most  of  the  digested  food  is  ab- 
sorbed by  the  stomach  and  intestines,  but  a  limited  amount  of 
liquid  is  absorbed  by  the  lining  of  mouth  and  pharynx  on  the 
way  down. 

Mucus. — A  secretion  of  the  glands  of  the  mucous  membrane,  and 
it  is  for  keeping  the  membrane  soft. 

Mumps. — An  inflammation  and  enlargement  of  the  parotid  glands. 

Nerve  Material. — There  are  three  kinds  of  nerve  material :  a  gray  in 
cells,  a  gray  in  fibres,  and  a  white  in  fibres.  The  gray  fibres 
are  connected  with  the  sympathetic  system. 

Neurilem'ma. — The  nerve  sheath  or  membrane  that  covers  a  fibre  of 
nerve.  Sometimes  it  is  interrupted,  as  in  Fig.  66,  III. 

Nitrogen. — A  negative  kind  of  gas.  It  has  few  characteristics,  and 
is  chiefly  noted  for  the  readiness  with  which  it  breaks  away 
from  its  combinations.  It  forms  a  part  of  all  easily  decaying 
organic  substances,  and  nearly  all  inorganic  explosives. 

Nitrogenous. — Containing  nitrogen,  as  nitrogenous  foods,  or  the 
proteids. 

Odontoid  Process. — The  peg-like  process  that  extends  from  the  front 
of  second  vertebra,  and  is  held  in  the  hollow  of  the  first  ver- 
tebra. It  enables  the  head  to  rotate. 


GLOSSARY.  257 

Organs  of  Corti. — In  the  cochlea  of  the  internal  ear  there  are  a 
number  of  little  rods  of  membrane  that  help  stimulate  the 
nerve  of  hearing  in  that  part  of  the  ear.  They  are  called  rods, 
or  organs,  of  Corti. 

Pan'creatin. — The  ferment  principle  of  the  pancreas  is  called  pan- 
creatin.  It  is  also  called  trypsin.  This  ferment  acts  on  fats. 

Papilla  (plural,  papillx). — Small  projections  of  the  upper  part  of  the 
true  skin  are  called  papillae.  The  teeth,  hair,  and  nails  grow 
from  them.  The  papillae  of  taste  are  of  three  kinds — filiform, 
fungiform,  and  circumvallate — and  can  easily  be  seen  on  the 
tongue. 

Pelvic  Girdle. — The  innominata  bones  are  so  called,  the  legs  being 
the  appendages. 

Pep'sin. — The  ferment  of  the  gastric  juice  is  called  pepsin,  and  it 
digests  proteids. 

Peptone. — Peptone  is  a  soluble  substance  made  by  gastric  juice  act- 
ing on  the  albuminoids  in  the  stomach. 

Pericardium. — The  serous  membrane  that  incloses  the  heart  is 
called  the  pericardium,  or  heart  sac. 

Perichon'drium. — The  fibrous  membrane  that  surrounds  cartilage. 

Periosteum. — The  bone  cover. 

Peritone'um. — The  serous  membrane  that  lines  the  walls  of  the 
abdomen. 

Petrous. — The  portion  of  the  temporal  bone  that  holds  the  essential 
organs  of  hearing  is  called  the  petrous  portion. 

Pinna. — The  cartilage  part  of  the  outer  ear,  sometimes  called  auricle. 

Plasma. — The  liquid  of  the  blood.  About  nine  tenths  of  it  is  water; 
the  remainder  is  albumen,  oil,  sugar,  salt,  soda,  and  waste 
material.  Plasma  carries  gas,  and  contains  the  nutritive  parts 
of  the  food. 

Proteids. — The  nitrogenous  foods  are  called  proteids.  They  are  lean 
meat,  eggs,  cheese,  milk,  pease,  beans,  and  grains,  and  any  veg- 
etable or  animal  tissue  containing  albumen,  fibrin,  or  casein. 

Protoplasm. —  A  simple  gelatinous  substance  found  in  growing  parts 
of  plants  and  animals.  It  is  the  primary  material  from  which 
cells  and  tissues  are  made. 

Pfy'alin. — The  ferment  of  the  saliva. 

Radius. — One  of  the  bones  of  the  forearm.  It  articulates  with  the 
carpal  bones,  and  is  the  bone  on  which  the  ulna  rotates. 

Rectum. — The  lower  part  of  the  large  intestine. 


258 


GLOSSARY. 


Reflex  Action. — Action  caused  by  impulse  from  a  nerve  center  with- 
out consciousness.  A  number  of  nerve  centers  of  the  spinal 
cord,  brain,  and  sympathetic  system  control  ordinary  motions 
independent  of  the  direction  of  the  mind. 

Respiration. — The  breathing  of  air  in  (inspiration)  and  out  (expira- 
tion) of  the  lungs.  When  mainly  thoracic  action,  as  in  women, 
it  is  called  thoracic  respiration ;  and  when  mainly  by  the  abdo- 
men, as  in  men  and  children,  it  is  called  abdominal  respiration. 

Respiratory  Food. — Fats  which  oxidize  readily  are  sometimes  called 
respiratory  foods. 

Re'te  Muco'sum. — The  inner  layer  of  cuticle  which  contains  the  pig- 
ment granules. 

Ru'gse. — The  folds  of  the  stomach. 

Sacrum. — The  five  consolidated  vertebrae  which  form  a  wedge 
between  the  parts  of  the  innominata. 

Saliva. — The  white,  frothy  alkaline  liquid  of  the  mouth.  Ptyalin,  a 
ferment,  is  part  of  it. 

Sarcolem'ma. — The  sheath  around  fibres  of  muscles. 

Scurvy. — A  skin  disease  brought  on  by  a  diet  of  salted  meats  and 
too  little  vegetables  and  acid  juices  of  fruits. 

Serous  Membrane. — A  white,  smooth  membrane  that  covers  organs 
and  lines  cavities  not  exposed  to  the  air.  It  is  pleura  of  lungs, 
pericardium  of  heart,  mesentery  of  intestines,  and  peritoneum 
of  walls  of  abdomen. 

Serum. — The  watery  liquid  of  the  blood  left  when  blood  coagulates. 

Sewer  Gas. — A  name  for  any  injurious  gas  that  comes  from  the 
drains  which  carry  off  waste  water.  Such  drains  should  be 
arranged  with  traps  and  ventilators  that  prevent  the  gas  from 
entering  houses. 

Shoulder  Girdle. — The  sternum,  scapula,  and  clavicle  form  the 
shoulder  girdle,  and  the  arms  are  its  appendages. 

Sighing. — A  deep  inspiration  followed  by  a  sudden  expiration,  caused 
by  fatigue,  bad  air,  or  some  mental  emotion. 

Sight. — The  defect  called  near,  or  short,  sight  is  where  the  eyeball 
is  too  long  and  the  image  is  not  formed  on  the  retina.  Far  or 
long  sight  is  where  the  eyeball  is  too  short.  Both  defects  to  be 
remedied  by  glasses. 

Sneezing. — A  spasmodic  involuntary  forcing  of  air  through  the  nose 
and  mouth,  caused  by  an  irritation  of  the  mucous  membrane. 

Snoring. — Hoarse  breathing  sounds,  caused  by  vibrations  of  palate. 


GLOSSARY.  259 

Soap. — A  substance  formed  by  the  union  of  fatty  acid  and  an  alkali 
(as  soda  or  potassa).  The  fatty  foods  are,  part  of  them,  made 
into  a  kind  of  soap  in  the  intestines. 

Sobbing. — A  convulsive  respiration. 

Stammering. — Irregular  action  of  vocal  organs.  When  not  caused 
by  malformation  of  organs,  it  is  the  result  of  defect  in  action 
of  nerve  centers,  and  can  be  overcome  by  deliberate  articula- 
tion. 

Suspensory  Ligament. — The  ligament  that  holds  the  crystalline  lens 
in  place.  The  ciliary  muscles  acting  on  the  choroid  coat  alters 
the  position  of  the  ligament  and  helps  in  accommodation. 

Syno'via. — A  thin  liquid  secreted  by  the  synovial  membrane  to  oil 
the  joints. 

Tabular  Bones. — Flat  bones. 

Tartar  of  Teeth. — A  hard  substance  that  attaches  itself  to  the  teeth, 
and  is  made  of  mucus,  animal  matter,  and  phosphate  of  lime. 

Tendon  of  Achilles. — The  strong  tendon  at  the  heel  of  the  gastroc- 
nemius  muscles.  Called  from  a  fabulous  story  of  Achilles,  a 
Grecian  hero,  being  held  by  the  heel  in  the  River  Styx,  and 
being  made  invulnerable  except  the  place  on  the  heel  by  which 
he  was  held. 

Tonsils. — Glandular  almond-shaped  bodies  on  the  sides  of  the  back 
of  the  throat. 

Trichina  Spiralis. — The  "  meat  worm,"  or  "flesh  worm,"  from 
measly  pork. 

Ulna. — The  smaller  bone  of  the  forearm. 

Urine. — The  excretion  of  the  kidneys  which  is  held  in  the  urinary 
bladder. 

Valves. — The  heart,  veins,  and  lymphatic  vessels  are  furnished  with 
valves.  In  the  last  two  vessels  they  are  pocket  valves.  The 
semi-lunar  valves  of  the  ventricles  are  also  of  this  kind,  but  the 
valves  between  ventricles  and  auricles  are  more  like  the  flaps  of 
a  tent.  One,  the  mitral,  or  bicuspid,  has  two  flaps,  and  the 
other,  tricuspid,  has  three  flaps. 

Ventricles. — There  are  three  organs  that  have  ventricles.  The 
brain  has  hollows  called  ventricles,  the  heart  has  two  ventricles, 
and  the  larynx  has  a  ventricle  on  each  side,  between  the  true 
and  false  vocal  membranes. 

Winking. — An  involuntary  action  of  the  eyelids  when  the  eyes  are 
threatened. 
17— P 


260  GLOSSARY. 

Wrist  Drop. — A  form  of  partial  paralysis  often  caused  by  lead  poi- 
soning. 

Yellow  Spot. — The  spot  on  the  retina  on  which  there  is  the  greatest 
amount  of  nerve  cones,  and  which  is  most  sensitive  to  light 
impulses. 


MISCELLANEOUS   FACTS. 


Amount  of  water  in  body  weighing  145  pounds :  108  pounds. 

Amount  of  food  daily:  16  ounces  meat,  19  ounces  bread,  3/^ 
ounces  fat,  52  ounces  water. 

Amount  of  saliva  in  24  hours :  about  3>£  pounds. 

Amount  of  gastric  juice  in  24  hours :  from  8  to  14  pounds. 

Amount  of  intestinal  juice  in  24  hours :  about  1  pound. 

Amount  of  pancreatic  juice  in  24  hours :  about  1}^  pounds. 

Amount  of  bile :  about  2%  pounds. 

Duration  of  digestion :  from  3  to  5  hours. 

Amount  of  blood  in  the  body  :  from  16  to  18  pounds. 

Size  of  red  corpuscles :  ^^W  of  an  inch. 

Size  of  white  corpuscles :  WTO  of  an  inch. 

Average  frequency  of  heart  beat  per  minute :  72. 

Velocity  of  blood  in  arteries:  about  16  inches  per  second. 

Length  of  time  for  circuit  of  blood :  about  20  seconds. 

Amount  of  air  in  and  out  at  each  respiration :  from  20  to  30  cubic 
inches. 

Amount  of  residual  air  always  in  lungs:  about  100  cubic  inches. 

Entire  amount  of  air  going  in  and  out  of  lungs  in  24  hours :  about 
400  cubic  inches. 

Composition  of  air:  nitrogen,  79.10;  oxygen,  20.81  per  100  parts. 

Amount  of  carbonic  acid  exhaled  in  24  hours :  14  cubic  feet. 

Rate  of  transmission  of  nerve  force :  about  100  feet  per  second. 

Length  of  spinal  cord:  16  to  18  inches;  weight,  ]}•£  ounces. 

Number  of  chemical  elements  in  body:  16  to  18. 


INDEX. 


^  PAGE. 

ABDOMEN 10 

ABDOMINAL         RESPIRATION 

(see  Respiration)  .  .  .  258 
ABSORBENT  SYSTEM  .  .  97-8 
ABSORPTION,  intestinal  .  .  75 

Lymphatic 97 

Lacteal 79 

Stomach 73 

By  skin 60 

Of  albuminoids  .     .     .     .172 

Of  fats 172 

Of  starches 172 

ACCOMMODATION  ....  246 
ACETABULUM  .  .  .  .  .  246 
ACHILLES'  TENDON  (see 

Tendon) 259 

ACID,      animal      (butyric, 
palmitic,  stearic)     .     .     .  246 

Mineral     (hydrochloric 
or  muriatic,  sulphuric)     .  246 

Vegetable   (acetic,   cit- 
ric, malic,  oxalic)    .     .     .  246 
ACTION  OP  THE  HEART    .  89, 246 

ADAM'S  APPLE 246 

ADIPOCERE 247 

ADIPOSE 247 

ADULTERATION 182 

AIR 208,210,247 

AIR  SACS 109 

AIR  TUBES 109 

ALBUMEN 247 

ALBUMINOIDS  .  247 


PAGE. 

ALCOHOL,  186;  brain,  192; 
heart,  192;  kidneys,  193; 
liver,  192;  lungs,  192; 
stomach,  192 ;  tissues, 
218;  will,  192,  227;  bev- 
erages, 188.  Causes  dis- 
eases (fatty  and  fibrous 
degeneration,  191 ;  gen- 
eral, special,  191).  Char- 
acteristics, 187.  In  large 
doses,  189.  Narcotic,  186. 
Not  a  food,  not  a  protec- 
tion against  heat,  cold, 
disease,  190.  Poison,  193. 
Stimulant,  186.  Uses  .  .  187 
ALIMENT  (food)  ....  247 
AMMENTARY  CANAL  .  62, 167, 247 

ALKALI 247 

ALKALINE  SUBSTANCES    .     .  247 

ALVEOLI 247 

AMYLOIDS 247 

ANATOMY 15 

ANKLE 9 

ANNULAR  LIGAMENT  .  39,  41,  247 

ANTIDOTES 197 

AORTA 247 

APPENDAGES  of  eye     .     .     .  248 

Of  ear 248 

Of  skin 248 

APPETITE 248 

AQUEOUS  HUMOR    ....  137 
ARACHNOID    (see    Coats  of 
Brain) 251 


262 


INDEX. 


PAGE. 

ARBOR  VITJE 248 

AREOLAR  TISSUE     ....  248 

ARTERIES 86 

ARTERY,  gastric     ....     94 

Pulmonary 94 

Renal 94 

ARTICLES  OF  DIET  TO  AVOID  185 
ARTICULATIONS  .  .  .  .28, 248 

ASPHYXIA 248 

ASSIMILATION     .     ,  • .     .     .  248 

ASTIGMATISM 248 

ATLAS  VERTEBRA  ....  30 
AUDITORY  CANAL,  nerve 

organ 134 

AURICLE  OF  HEART  ...  88 
AXIS  VERTEBRA 30 

B 

BALL  AND  SOCKET  JOINT     .     29 

BANTING 248 

BATHING 161 

BEEF 173 

BEEF  TEA 174 

BICEPS  MUSCLE  ....  39 
BICUSPID  VALVE,  89 ;  teeth  .  68 
BILATERAL  SYMMETRY  .  .  248 

BILE 76,248 

BITTERS 195 

BLADDER,  gall,  urinary  .  .  248 
BLEEDING  (hemorrhage)  .  204 

BLIND  SPOT 138 

BLOOD 83 

BLOOD  CORPUSCLES  (see  Cor- 
puscles)   83 

BLUSHING 249 

BODY 9 

BONE,  20;  composition,  25; 
cover,  24;  color,  24; 
classes,  21;  structure,  24; 

uses 31 

BRAIN  .  .  112 


PAGE. 

BRAIN  BOX    ......     21 

BRANDY    .......  188 

BREAD      .......  173 

BREATHING    (see     Respira- 
tion)     .......  258 

BREASTBONE  (sternum)  .    18-20 
BRIGHT'S  DISEASE  ....  203 

BROKEN  BONES  .....  154 

BRONCHUS     ......  249 

BRONCHIAL  TUBES  .     .     109,  249 
BUNION     .......  249 

BURNS  ......     166,  249 

.......  249 


c 

.......  249 

CAFFEIN    .......  249 

CANAL,  alimentary,  62,  247; 
auditory,  134  :  lachrymal, 
136;  spinal     .....  115 

CANALICULI  ......  250 

CANINE  TEETH  .....     67 

CANNED  MEAT    .....  177 

CAPILLARIES      .....     85 

CAPSULAR  LIGAMENT  ...     29 
CARBOHYDRATES    ....  250 

CARBON    .     .     .  '  .     .     .     .250 

CARBONATE  OF  LIME  ...     26 
CARBON  DIOXIDE    ....  209 

CARDIAC  OPENING  ....     70 

CARPAL  BONES  .....     22 

CARTILAGE    .....      9-12 

CASEIN      .......  172 

CATALEPSY    ......  250 

CAUDA  EQUINA  .....  115 

CAVITIES  OF  BODY  AND  HEAD.      9 
CELLS  ........     12 

CELLULAR  TISSUE  (see  Are- 
olar  tissue)     .....  248 

CELLULOSE    ......  250 

CEMENT    .  .    67 


INDEX. 


263 


PAGE. 

CENTRUM  OF  VERTEBRAE  .     .     33 

CEREBELLUM 113 

CEREBRO-SPINAL  SYSTEM  115,116 

CEREBRUM 113 

CERUMEN  (ear  wax)  .  .  .250 
CERVICAL  VERTEBRAE  ...  23 
CILIARY  MUSCLES,  processes.  250 

CHAPS 162 

CHANGES  IN  BLOOD     .     .     .  101 

CHEST 9 

CHILDREN'S  BONES      .     .     .  153 

CHLORAL 250 

CHLOROFORM 250 

CHORDS    TENDINE^      (see 
Columnse  carnese)  .     .     .  251 

CHOROID 137 

CHYLE 75 

CHYLIFICATION  (digestion)  .     74 

CHYME 74 

CHYMIFICATION  (digestion)  73,  74 

CILIA 105 

CIRCULATION  OF  BLOOD  .  .  83 
ClRCUMVALLATE  PAPILLAE 

(see  Papilla) 257 

CLASSES  OF  BONES.  ...  21 

CLAVICLE 20 

CLOTHING 164 

COAGULATION 85 

COATS  OF  THE  BRAIN  .     .     .  251 

COCAINE 251 

COCCYX    .     .     .     .     20,  23,  251 

COCHLEA 133 

COCOA 177 

COFFEE 176 

COLD  FEET 206 

COLDS 165 

COLON  (see  Intestines)    .  81,  255 
COLOR    BLINDNESS   (Dalton- 
ism)       251 

COLUMNS  CARNEY  .  .  .  251 
COMPRESSING  CHEST  .  .  .  214 


PAGE. 

COMPOUNDS 167 

CONCHA 133 

CONDIMENTS 175 

CONJUNCTIVA 251 

CONNECTIVE  TISSUE  ...  45 

CONSTIPATION 251 

CONSUMPTION 221 

CONVOLUTIONS  OF  BRAIN  .  113 

COOKING 178 

CORNEA 136 

CORNS 166 

CORPUS  CALLOSUM  ....  251 
CORPUSCLES,  of  blood,  83; 

of  touch,  128 ;  of  taste  .  .  251 

COSMETICS 162 

COSTAL  RESPIRATION  (see 

Respiration) 258 

CRANIAL  NERVES  ....  121 
CRANIUM  (brain  box)  ...  21 
CRYSTALLINE  LENS  .  .  .  137 

CUTICLE 49 

CUTIS  VERA  (true  skin)  .  .  52 

D 

DALTONISM  (see  Color  blind- 
ness)      251 

DANDRUFF 50 

DEGENERATION,  fatty, fibrous 

158,  191,  199 

DELIRIUM  TREMENS  .  .  .  251 
DELTOID  MUSCLE  ....  41 

DENTINE 67 

DERMIS 52 

DIAPHRAGM 45, 104 

DIARRHOEA 198 

DIASTYLE  (see  Action  of  the 

heart) 246 

DIET 173, 174, 185 

DIGESTIBILITY  OF  FOODS.     .  252 

DIGESTION 181 

DIGESTIVE  FLUIDS  ....     81 


264 


INDEX. 


PAGE. 

DIGESTIVE  PROCESS     ...     64 
DIGESTIVE  ORGANS  ....     63 

DIPSOMANIA 252 

DISEASE,  151 ;  of  alimentary 
canal,  198 ;  of  bones,  155 ; 
of  circulatory  system,  202 ; 
of  kidneys,  206;  of  lungs 
and  throat,  217,  220;  of 
muscles,  157;  of  nervous 
system,  233;  of  skin  .  .  166 

DISTILLATION 188 

DORSAL  VERTEBRAS     .     .•    .     23 

DRAINAGE 252 

DREAMS 252 

DRUM  OF  EAR  (see  Ear^ .     .  133 
DUCT,  pancreatic,  63;  bile, 

63;  salivary 65 

DUCTLESS       GLANDS       (see 

Glands) 254 

DUODENUM  (see  Intestine)    .  252 
DURA  MATER  (see  Coats  of 

brain) 251 

DYSPEPSIA 198 

E 

EAR,  bones 133 

EGGS 172,  178 

ELBOW  JOINT 252 

ELEMENTS 167 

EMETICS 197 

EMOTION 252 

EMULSION 252 

ENAMEL 66 

ENDOLYMPH 252 

ENERGY 169 

EPIDERMIS 48 

EPIGLOTTIS 106 

ETHNOID  BONE 253 

EUSTACHIAN  TUBE  ....  253 
EXCESSES  .  232 


PAGE. 

EXCRETION 57 

EXCRETORY  ORGANS    .     .     .  253 

EXERCISE 156 

EXPIRATION    (see    Respira- 
tion)   258 

EXTENSORS 41 

EYE 135 

F 

FACE 7 

FAINTNESS 204 

FAT 46 

FATS 253 

FATTY  DEGENERATION     .     .  191 
FENESTRA,  ovalis,  rotunda .  253 

FERMENTATION 187 

FERMENTS 253 

FIBRES  OF  MUSCLES    ...     37 

FIBRILS 40 

FIBRIN 253 

FIBULA 253 

FILIFORM  PAPILLA  (see  Pa- 
pillae)      257 

FISH 173 

FLEXORS 41 

FLOATING  RIBS 39 

FLUIDS 12 

FOLLICLES 253 

FOOD 170 

FORAMEN 24,  253 

FRECKLES 51 

FRONTAL  BONE  .     .     .     .    18,  20 

FRUITS 175 

FUNCTION  OF  BRAIN,  medulla 

oblongata,  spinal  cord      .  119 
FUNNY    BONE    (see    Elbow 
joint) 252 

FUNGIFORM       PAPILLA       (866 

Papilla) 257 

FURRED  TONGUE         ...  185 


INDEX. 


265 


PAGE. 

GALL  (see  Bile) 248 

GALL  BLADDER 248 

GANGLION 254 

GASTRIC,     digestion,     181; 
fever,    198;    glands,    73; 

juice 73 

GERM  DISEASES      ....  218 
GLANDS,  intestinal,  74;  gas 
trie,     73;     kidneys,    99; 
lachrymal,      136;      lym- 
phatic,    99;     liver,     75; 
meibomian,  256;  oil,  58; 
pancreas,  75 ;  parotid,  65 ; 
salivary,  64;  spleen,  100; 
sublingual,  65 ;  submaxil- 
lary,  65;  sudoriparous  or 

sweat 254 

GLIDING  JOINTS 29 

GLOTTIS 106 

GLUCOSE 254 

GLUTEN 172 

GLYCERINE 254 

GLYCOGEN 76,  254 

GRAINS 172 

GRAPE  SUGAR  (see  Glucose)  254 
GRAY  NERVE  MATTER  .  114,  225 
GULLET 63,  69 

H 

HABITS  TO  AVOID  .  .  153,  231 

HAEMOGLOBIN 254 

HAIR,  follicle,  53;  structure  54 

HASHEESH 254 

HAVERSIAN  CANAL  (see 

Bone) 26,  249 

HEAD 7 

HEALTH 151 

HEARING,  nerve,  organs, 

sense  .     -     132-135 


PAGE. 

HEART,  auricles,  ventricles, 
89;  muscle,  44;  motions, 

90;  valves 89 

HEAT 208 

HEMORRHAGE  (see  Bleeding)  204 
HEPATIC      ARTERY,      capil- 
laries, cells,  veins  .   94-95-96 

HEREDITY 152 

HIGH-HEELED  SHOES  .     .     .  154 

HINGE  JOINT 28 

HIP  BONES 32 

HIP  JOINT 29 

HUMERUS  ....  18,  19,  25 
HUMORS  OF  THE  EYE  .  .  139 

HUNGER 62 

HYDROCARBONS  (see  Fats).  253 
HYGIENE  .....     .15,  151 

HYOID  BONE 255 

I 

IDEAS 118 

ILEUM 63,244 

INCISORS 67 

INCUS •    ...  133 

INDIGESTIBLE  SUBSTANCES  .  255 

INDIGESTION 255 

INHERITANCE  (see  Heredity)  152 
INNOMINATA,  bone ....  20 
INORGANIC  FOOD  ....  170 

INSALIVATION 255 

INSENSIBLE  PERSPIRATION     .     59 
INSPIRATION    (see    Respira- 
tion)       258 

INTERNAL  EAR 134 

INTESTINAL  CANAL.     ...     63 
INTESTINES,    coats    of,    74; 
digestion  of,  79 ;  folds  of, 
74;  glands  of,  74;  large, 
79 ;  length  of,  motion  of, 
small,  74;  villi  of    ...     77 
IRIS  .     •  137 


266 


INDEX. 


IVY  POISON 


PAGE. 

14,  164 


JAWS,  lower,  upper    ...     20 
JEJUNUM  (see  Intestines).     .     63 
JOINT  OIL  (see  Synovia)  .     .     28 
JOINTS,  28  ;  ball  and  socket, 
29  ;  immovable,  30  ;  hinge, 
28;  movable,  29;  gliding, 
29  ;  pivot,  30  ;  suture  .     .     30 


KIDNEYS  ......  99,  206 

KINDS  OF  DIGESTION  ...     79 
KNEE  CAP     ......     20 

KNEE  JOINT  ......     28 

KOUMISS    .  .  255 


LABYRINTH 133 

LACHRYMAL  CANALS,  duct, 

gland,  lake 136 

LACTEALS 78,  97 

LACTOSE 255 

LACUNA  (see  Bone)  .  .  .  249 

LARYNX 106 

LEAD  POISON 163 

LEGUMIN 255 

LEGUMINOUS 255 

LENS 255 

LIGAMENTS 20 

LIMBS 9 

LIVER 75,  95 

LONG  SIGHT  (far  sight)  (see 

Sight) 258 

LUMBAR  VERTEBRA  ...  23 
LUNGS,  110;  position,  111; 

elasticity,  111 ;  sacs  .  .109 
LUNULA 256 


PAGE. 

LYMPH 256 

LYMPHATIC  ABSORPTION  .         97 


M 

MALAR  BONE      .     .     .     .    18,  19 

MALLEUS 133 

MARROW,  red,  yellow.     .     .  256 

MASSAGE  .     .    • 256 

MASTICATION 71 

MASTOID  PROCESS  ....  256 
MAXILLARY  BONES  ....  20 

MEATS 173 

MEDULLA  OBLONGATA  .  .  .  256 
MEMBRANA  TYMPANI  .  .  .  133 
MESENTERY  (see  Serous 

membrane) 258 

METACARPAL      .     .     .     .    20,  22 

METATARSAL 20 

MILK  TEETH 68 

MITRAL  VALVE 90 

MOLAR  TEETH 68 

MORPHINE 194 

MOTOR  NERVE 117 

MOUTH   AND   PHARYNX    AB- 
SORPTION     256 

Mucous  GLANDs(see  Glands)  254 

MUCOUS  MEMBRANE      ...       49 

Mucus 256 

MUMPS 256 

MUSCLES,    36;    action,    40; 
contractility,   36;    shape, 

40;  structure 37 

MUSCULAR  TRAINING  ...  42 
MYOPIA  (see  Sight)  .  .  .  258 

1ST 

NAILS 55 

NARCOTICS  ....  193,  227 
NASAL  CAVITY 69 


INDEX. 


267 


PAGE. 

NERVE     CELL,     114;    fibre, 
material,   256;    function, 
116  ;  motor,  117  ;  sensory, 
117;    gray,    114;    white, 
114;  educated,  118;  cross- 
ing of    .......  119 

NERVOUS  SYSTEM    ....  112 

NEURILEMMA      .....  256 

NICOTINE  .......  196 

NITROGEN  .......  256 

NITROGENOUS     POODS     (see 
Proteids)    ......  257 

NOSE  BLEED  ......  204 

o 

OCCIPITAL     FORAMEN      (see 
Foramen)  ......  253 

ODONTOID  PROCESS      .     .     .  257 
(ESOPHAGUS  .....    63,  71 

OIL  GLANDS   ......     57 

OLFACTORY  LOBES,  nerves    .  131 
OLIVE  OIL  .......  174 

OPIUM  ........  193 

ORBIT  ........  140 

ORGANIC  FOOD   .....  170 

ORGANS  OF  CORTI    ....  257 

OSMOSIS  (osmose)  .     .     .79,  109 
OSSICLES  (ear  bones)  .     .     .  133 
OXIDATION     ......  168 

OXYGEN    .......  110 


PALATE,  hard,  soft      ...     69 
PALPEBR^S  (eyelids)    .     .     .  135 
PALPITATION  OF  HEART    .     .  159 
PANCREAS      ......     75 

PANCREATIC  JUICE  ....     75 

PANCREATIN  ......  257 

PAPILLAE,  257;  touch,  52; 
taste,  129;  of  teeth,  53;  of 
skin,  53  ;  of  nails,  56  ;  hair  53 


PARALYSIS     .     . 
PAREGORIC    .     . 
PARIETAL  BONE  . 
PAROTID  GLAND 
PELVIC  CAVITY   . 


PAGE. 

.  233 

.  193 

18,  20 

.     65 

9 


PELVIC  GIRDLE 257 

PEPSIN 257 

PEPTONES 257 

PERICARDIUM 257 

PERICHONDRIUM      ....  257 
PERILYMPH       (see      Endo- 

lymph) 252 

PERIOSTEUM 257 

PERISTALTIC  MOTION    ...     73 

PERITONEUM 257 

PERMANENT  TEETH      ...     69 

PERSPIRATION 59 

PHALANGES 20,  22 

PHYSIOLOGY 15 

PIA  MATER  (coats  of  brain) 

' 112,  251 

PIGMENT  CELLS      ....     51 

PINNA  (ear) 133 

PLASMA 257 

PLEURA Ill 

PLEURISY 221 

PNEUMO-GASTRIC  NERVE  .     .  216 

POISONS 197 

PORTAL  SYSTEM,  vein      .    94,  95 
PREMOLAR  (bicuspid)       .     .     68 

PROTEIDS 257 

PROTOPLASM 257 

PTYALIN 258 

PULMONARY       CIRCULATION, 

92 ;  artery,  91 ;  vein    .     .     91 

PULP  CAVITY 67 

PULSE 87 

PUPIL  OF  EYE 136 

PYLORUS 72 


268 


INDEX. 


,  PAGE. 

RADIUS     .......  258 

RED  CORPUSCLES  (see  Cor- 

puscles)    ......    83 

RED  MARROW  (see  Marrow).  256 
RECEPTACULUM  CHYLII    .  14,  98 
REFLEX  ACTION  .....  258 

REGULARITY  IN  EATING  .  .  181 
RESPIRATION,  103;  abdom- 

inal, 258;  thoracic  .     .     .258 
RESPIRATORY  FOOD     .     .     .  258 
REST    ........  157 

RETINA     .......  138 

RETE  MUCOSUM  .....  258 

RIBS     .     .     ......     31 

RICKETS   .......  155 

258 


s 

SACRUM    .......  258 

SALIVA      .......  258 

SALIVARY  GLANDS  ....     64 

SALIVIN-PTYALIN     .        .     .  258 
SALT    ........  170 

SARCOLEMMA    .....     258 

SCAPULA  .......     21 

SCLEROTIC     ......  136 

SCURVY     .......  258 

SEBACEOUS  GLANDS  (see 

Glands)      ......  254 

SEDATIVES  (narcotics)  .  .  194 
SEMICIRCULAR  CANALS  (see 

Canals)      ......  249 

SEMILUNAR  VALVES      .     .   89,  90 
SENSATION     ....     118,  130 

SENSES,  special      ....  127 

SENSORY  NERVES    ....  117 

SEROUS  MEMBRANE      .     .     .  258 
SERUM  OF  BLOOD    ....  258 

SEWER  GAS    ......  258 

SHAFT  OF  BONE  .  21 


PAGE. 

SHOULDER  GIRDLE  ....  258 

SIGHING 258 

SIGHT,  far,  near     ....  258 

SlGMOID  FLEXURE    ....       63 

SKELETON 18,  19 

SKIN 48 

SKULL 21,  31 

SLEEP 229 

SMELL 131 

SNEEZING 259 

SNORING 259 

SOAP 259 

SOBBING 259 

SOOTHING  SYRUPS  ....  193 

SOUND 135 

SPHENOID  BONE 20 

SPINAL  COLUMN 23 

SPINAL  CORD 115 

SPINOUS  PROCESSES     ...  24 

SPLEEN 100 

SPRAINS 155 

STAMMERING 259 

STAPES 133 

STARCHES 172 

STARVATION 168 

STERNUM 20 

STIMULANTS  ....    175,  186 

STOMACH  .......  72 

STRIPED  MUSCLE     ....  40 

SUBLINGUAL       GLANDS       (866 

Glands) 254 

SUBMAXILLARY     GLANDS  (S66 

Glands) 254 

SUDORIFEROUS  =  Sudoripa- 
rous glands  (see  Glands)  .  254 

SUGAR 172 

SUNBURN 51 

SUPERFLUOUS  FAT  (see  Bant- 
ing)   248 

SUSPENSORY  LIGAMENT     .     .  259 ' 
SUTURES   .  30 


INDEX. 


269 


PAGE. 

SWEAT  GLANDS  (see  Glands)  254 
SWEET  BREAD  (see  Pancreas)  75 
SYMPATHETIC  SYSTEM  .  .  .  122 

SYNOVIA 259 

SYNOVIAL  MEMBRANE  .  .  .  28 
SYSTEMIC  CIRCULATION  .  .  92 

SYSTEMS 13 

SYSTOLE  (action  of  heart)    .  246 


TABLES,  bone,  20;  muscle, 
41 ;  breathing  organs,  111 ; 
special  senses,  140;  skin, 
61;  digestive  organs,  81; 
alcohol,  193 ;  antidotes  .  197 
TABULAR  BONES  ....  259 

TARSAL  BONES 20 

TARTAR,  of  teeth    .     .     .     .259 

TASTE 129 

TASTE  CORPUSCLES  (see  Cor- 
puscles)      83 

TEARS 136 

TEETH,  66;  milk,   69;  per-, 
manent,  69;  incisor,  67; 
canine,  67;  bicuspid,  68; 
molar,  68;  structure,  67; 

hygiene  of 186 

TEMPERATURE 208 

TEMPORAL  BONES    ....     21 

TENDONS 11,  43 

THEINE 176 

THIGH  BONE 20 

THORACIC  DUCT  ....  79 
THYMUS  GLAND  (see  Glands)  254 
THYROID  GLAND  (see  Glands)  254 

TIBIA 20 

TIGHT  LACING 214 

TISSUES 12 

TOBACCO 195,  217 

TONGUE 66,  129 

TONSILS    ,  .  259 


PAGE. 

TRACHEA 104 

TRICEPS  MUSCLE      ....  41 

TRICHINA  SPIRALIS  .     .    159,  259 

TRICUSPID  VALVE    ....  90 

TRYPSIN  (pancreatin)      .     .  257 

TURBINATED  BONE  ....  20 

TYMPANUM    ....    133,  134 

U 

ULNA 259 

UNSTRIPED  MUSCLE     ...  40 

URINARY  BLADDER      .     .     .  248 

URINE  .                                  .  259 


VALVES  OF  HEART  (bicus- 
pid =  mitral,  tricuspid, 
semilunar),  259;  of  lym- 
phatics, of  veins  .  .  .  259 

VEINS 88,  94 

VENA  CAVA,  inferior,  88; 
portal  vein,  94;  superior  .  88 

VENTILATION 210 

VENTRICLES  OF  BRAIN  .  .  259 
VERMICULAR  MOTION  ...  72 
VERMIFORM  APPENDAGE  .  .  80 

VERTEBRAE 33 

VERTEBRAL  COLUMN  ...  23 
VESTIBULE  OF  EAR  .  .  .  133 

VILLI 78 

VITREOUS  HUMOR    ....  137 

VOCAL  CORDS 108 

VOLUNTARY  MUSCLES  ...  36 
VOMER 20 

w 

WALKING 156 

WARM  BATHS     .     .     .     .  •  .  161 
WATER,  170;  impurities  of  .  171 
WHITE  CORPUSCLES  (see  Cor- 
puscles)       83 


270 


INDEX. 


PAGE. 

WHITE  NERVE  MATTER  (see 
Nerve  material)      .     .     .  256 

WINDPIPE 104 

WINKING 260 

WORRY  .  229 


PAGE. 

WOUNDS 205 

WRIST  DROP  .  .  260 


YELLOW  SPOT 


260 


GYMNASTICS. 


GYMNASTICS. 


THis  chapter  is  introduced  to  furnish  an  order  of  gym- 
nastic exercises  convenient  to  be  observed  in  the  school 
room.  As  the  stationary  desks  in  common  use  leave  lim- 
ited room  for  practice,  the  free  hand  exercises  (i.  e.  those 
without  apparatus)  are  most  readily  available.  Still, 
many  of  the  movements  can  profitably  be  carried  out  with 
dumb-bells.  While  no  originality  is  claimed,  except  in 
arrangement,  it  would  be  difficult  to  credit  the  exercises 
to  their  originators,  as  they  are  described  in  most  of  the 
books  devoted  to  gymnastics,  and  seem  to  be  common 
property. 

Additional  exercises  can  be  improvised  by  combining 
the  various  movements  mentioned  in  the  following  table 
with  the  different  positions  given  in  the  same  table.  Also, 
by  hand,  head,  or  arm  movements,  with  charges  in  differ- 
ent directions,  or  by  alternation  of  parts  of  two  related 
exercises,  as  is  illustrated  once  or  twice  in  the  third  series. 

The  great  secret  of  continued  interest  in  gymnastic 
exercises  is  the  requirement  of  strict  accuracy  in  their 
performance.  By  this  is  meant  exactness  of  time  at  which 
a  movement  is  performed,  and  perfection  in  the  accom- 
plishment of  all  the  details  of  the  movement. 

Time  of  Movement.  Unless  otherwise  stated,  the 
movements  are  to  be  made  on  the  accented  beat  of  the 
music,  while  on  the  unaccented  beat  the  part  moved  is 
brought  back  to  position.  To  secure  exactness,  it  is  nec- 
essary to  have  the  movements  made  very  quickly,  leaving 
an  appreciable  time  for  the  part  moved  to  remain  at  rest 


274 


GYMNASTICS. 


in  the  position  assumed.  The  same  direction  is  to  be 
observed  in  recovery  of  position.  In  some  of  the  exer- 
cises, double  time  is  to  be  taken.  In  these  cases,  the 
movements  and  recovery  of  position  are  all  made  on  the 
accented  beat,  the  time  between  being  used  as  rests.  This 
will  be  indicated  by  the  direction,  Double  Time. 

Accuracy  of  position  implies  an  absolute  sameness 
of  position  on  the  part  of  all  the  individuals  of  the  class. 
When  the  direction  is  to  thrust  the  arm  upward,  for  in- 
stance, it  is  expected  that  the  hand,  forearm,  and  upper 
arm  will  form  a  vertical  straight  line,  the  elbow  and  wrist 
being  unbent. 

Music  adds  much  to  the  enjoyment  of  these  exercises, 
either  a  march  or  galop  being  suitable.  But  while  learn- 
ing a  new  movement,  counting  in  clear,  quick  tones  will 
be  found  most  effective.  The  counts  will  be  from  one  to 
eight,  and  at  first  the  word  "and"  may  be  introduced 
between  the  counts  to  mark  the  instant  for  recovery  of 
position;  as,  One,  and;  Two,  and;  etc. 

Dress.  The  dress  should  be  such  as  to  impede  as  little 
as  possible  the  free  movement  of  the  muscles.  For  girls, 
a  blouse  waist  is  recommended,  with  long,  loose  sleeves 
coming  high  up  on  the  shoulders,  and  sufficient  length 
under  the  arm  to  allow  the  arms  to  be  raised  easily  to  a 
vertical  position.  In  dresses  designed  for  calisthenic 
practice,  the  bottom  of  the  skirt  should  not  come  within 
six  or  seven  inches  of  the  floor.  Corsets  or  whalebones 
should  not  be  worn. 

Pull  breathing.  The  exercises  will  fail  almost  wholly 
of  their  desired  result  unless  accompanied  by  full,  deep 
breaths. 

Ventilation.  As  exercise  quickens  breathing,  there 
is  need  of  an  increased  supply  of  fresh  air.  Open  win- 


GYMNASTICS.  275 

dows  during  the  time  of  practice  will  not  be  found  dan- 
gerous; the  danger  from  draughts  is  after  the  exercise  is 
finished.  Sixty-five  degrees  Fahrenheit  is  a  temperature 
quite  high  enough  during  active  work. 

General  position.  Chest  expanded,  head  erect,  chin 
drawn  in,  heels  touching,  and  feet  at  an  angle  of  sixty 
degrees. 


TABLE    OF    POSITIONS   AND    MOVEMENTS. 


POSITIONS. 

1.  Closed  hands  on  chest  near  shoulder,  palms  facing 
each  other,  elbows  close  to  the  body.     Figure  1. 

2.  Hands  on  hips,  fingers  front.     Figure  4. 

3.  Hands  upon  shoulders,  upper  arms  horizontal  at 
side.     Figure  9. 

4.  Hands  closed  and  under  armpits.     Figure  17. 

5.  Hands  clasped  behind  head.     Figure  23. 

6.  Arms  outstretched  at  side,  hands  closed,  palms  for- 
ward. 

7.  Arms  held  vertically  upwards,  hands  closed. 


MOVEMENTS. 

I  wrists, 
elbows, 
head, 
body, 
^  ankle. 

( directly, 
forward 


Twisting 


arms,  Charges,  (obliquely, 

hands,  or        <[  backward    \  directly, 

head,  Steps.  |  obliquely. 

Isidewise. 


18— P 


276 


GYMNASTICS. 


Swinging  the  arms  in  a  vertical,  horizontal,  or  oblique 
plane,  is  also  a  movement  of  value,  not  included  in  the 
above  schedule. 

When  the  positions  in  two  successive  exercises  differ, 
the  change  should  be  made  on  the  last  unaccented  beat 
of  the  first  exercise. 

FIRST  SERIES. 

1.  First  position,  Figure  1.  Thrust 
the  right  hand  downward  four  times 
in  succession;  the  left  hand  four  times. 
Thrust  right  and  left  hands  downward 
alternately  four  times;  both  hands 
together  four  times  (Figure  24). 


Fig.  1. 

2.  In   the  same  order,  thrust  hands 
outward  at  sides.     Figure  2. 

3.  Thrust  upward,  the  arm  assum- 
ing a  position  strictly  vertical.     Same 
order.     Figure  14  shows  left  arm   in 
this  position. 


Fig.  2. 


GYMNASTICS. 


277 


4.  Thrust  forward,  bringing  the  arms  to 
a     horizontal     position     level     with     the 

shoulders.  Figure  3.  At  the 
close  of  the  fourth  exercise,  as- 
sume second  position.  Figure  4. 

5.  At  the  accented  beat  rise  on  toes,  and 
on  the  unaccented  beat  let  the  heel  touch 
the  floor.     Eight  times. 

6.  Bend  the  knees,  thus  sinking  from  four 
to  six  inches,  but  keeping  the  upper  part  of 
the  body  vertical.     Eight  times. 


Fig.  3. 

7.  Raise  the  shoulders  eight  times. 

8.  Thrust  elbows  as  far  back  as  pos- 
sible   eight    times.       This    movement 
must  be  performed  with  care  at  first, 
as   there   is   danger   of    straining   the 
muscles  of  the  chest.     At  close  of  exer- 
cise drop  hands  at  the  sides. 

9.  Keeping   the  arms    straight   and 
elbows  stiff,  bring  the  hands  forward 

and   up   until  the  arms  are  vertical;  Fig.  4. 

then  lower  by  the  sides.  Double  time,  each  movement 
and  recovery  of  position  to  be  performed  on  the  accented 
beat.  Four  times. 

10.  Palms  toward  the  front.    On  the  accented  beat,  open 
the  fingers  wide.     On  the  unaccented  beat  close  them. 


278 


GYMNASTICS. 


Perform  this  finger  movement  four  times  in  succession, 
bringing  the  hands  to  the  chest,  first  position,  on  the 
fourth  unaccented  beat. 

11.  Same  as  above,  except  that  on  the  first  accented 
beat  the  hands  are  to  be  thrust  outward  at  the  sides, 
palms  forward,  and  at  the  same  time  the  fingers  are  to  be 
opened. 

12.  Same  as  above,  thrusting  the  hands  directly  up- 
ward, palms  forward. 

13.  Same  as  preceding,  thrusting  the  hands   directly 
forward,  palms  facing  each  other. 

14.  The  hands  being  tightly  closed,  thrust  them  simul- 
taneously downward,  then  outward,  then  upward,  then 
forward,    twisting    the    arms    inward    each    time    and 
performing   the   action   vigorously. 

Bring  the  hands  to  the  chest  after 
each  movement.  Repeat.  Take 
second  position. 


15.  Double  time  in  this  exercise 
and  in  all  the  remaining  exercises 
of  this  series.  The  left  foot  is  kept 
stationary  during  this  exercise. 
The  right  foot  is  carried  in  succes- 
sion, with  a  short,  springing  step, 
(1)  directly  forward,  (2)  diago- 
nally forward  to  the  right,  (3)  to 
the  right,  (4)  diagonally  backward, 
(5)  backward,  (6)  backward  to  the 
left,  (7)  to  the  left,  Figure  5,  and 
last  (8)  in  front  to  a  position  in 
line  with  the  left  foot.  Figure  6. 


Fig.  5. 


GYMNASTICS. 


279 


Fig.  6. 


After  each  movement  the  right  foot 
is  brought  back  to  its  original  posi- 
tion. Care  must  be  taken  that  the 
body  be  not  twisted  before  the 
seventh  movement.  In  the  seventh, 
the  body  is  twisted  to  the  right,  so 
that  the  pupil  faces  exactly  to  the 
side  of  the  hall ;  the  right  foot  is 
carried  back  of  the  left  to  its  posi- 
tion. 


16.  Bend  the  head  to  the  right 
side,  recovering  position  on  second 
accented  beat.  On  the  third,  bend 
the  head  to  the  left,  recovering 
position  on  the  fourth.  Figure  7. 
Repeat  one  or  three  times. 


Fig.  7. 


280 


GYMNASTICS. 


17.  Turn  the  head  to  the  right  and 
then  to  the  left.    Figure  8.    Repeat 
one  or  three  times. 

18.  Bend  the  head  forward  and 
then  backward.    Repeat  one  or  three 
times. 

19.  Bend  the  head  forward,  to  the 
right,  backward,  to  the  left,  recover- 
ing position  after  each  movement. 
Repeat  in  reverse  order. 

20.  Steps  with  left  foot  as  in  Exer- 
cise 15.    At'the  close  of  exercise  rest 
for  eight  beats,  on  the  eighth  unac- 
cented beat  assuming  position  for 
second  series. 


Fig.  8. 

SECOND  SERIES.  - 

1.  Hands  on  shoulders.  The 
elbows  should  be  out  at  sides 
and  on  a  level  with  the  shoul- 
ders. Figure  9.   Thrust  right 
hand  down  four  times,  left  four 
times,  alternately  four  times, 
together  four  times.     At  each 
recovery  of  position,  the  elbowrs 
must  be  on  a  level  with  the 
shoulders. 

2.  Same   position.      Thrust 
hands    outward    at    sides   in 
same  order. 


Fig.  9. 


GYMNASTICS. 


281 


3.  Same  position.  Thrust  hands  upward.  Arms  vertical. 

4.  Same  position.    Thrust  forward.    In  these  four  exer- 
cises care  must  be  taken  at  each  recovery  of  position  to 

bring  the  shoulders  and  elbows  back 
to  the  exact  position  first  assumed. 
If  this  is  done,  these  exercises  will 
be  found  very  valuable  in  developing 
the  muscle  just  in  front  of  the  shoul- 
der, and  in  raising  and  developing 
the  chest.  The  hands  are  kept  open. 
5.  Second  position.  Double  time 
in  this  and  the  six  following  exer- 
cises. Bend  the  body  from  the  waist 
to  the  right  side  as  far  as  possible. 
Figure  10.  Recover  position. 
Bend  the  body  to  the  left  in  the 
same  way.  Alternate,  two  or  four 
times  to  the  right  and  two  or  four 

times  to  the  left. 

.yipr 

Fig.  10. 


282 


GYMNASTICS. 


6.  Twist  the  body  four  or  eight 
times  alternately  to  the  right  side 
and  to  the  left  side,  keeping  the 
lower  part  of  the  body  as  steady  as 
possible.  Figure  11. 


Fig.  11. 

7.  Bend  the  body  four  or  eight  times  alternately  forward 
and  backward  as  far  as  possible. 

8.  Bend  forward,  to  the  right,  backward,  to  the  left, 
recovering  position  between  the  movements.      Repeat  in 
reverse  order. 

9.  Spring  diagonally  forward  with  right  foot  and  sway 
by  bending  right  and  left  knee  alternately  on  accented 
beat,  resuming  position  on  fourth  unaccented  beat. 


GYMNASTICS. 


283 


Fig.  12. 


10.  Same  as  preceding,  begin- 
ning with  left  foot.    Figures  12 
and  13. 

11.  Hands  closed  and  hanging 
at  sides.  Elbows  stiff.    Raise  the 
right  arm  at  the  side  to  a  hori- 
zontal or  vertical  position  four 
times,  left  arm  four  times,  alter- 
nately four  times,  together  four 
times. 

12.  First  position.     Common 
time.     Thrust  right  hand  down 
and  bring  it  back  to  position; 
left  hand  the  same;  clap  hands 
quickly  six  times,  twice  to  each 
half  count.     This,  with  recovery 
of    position,    will    occupy    four 
counts. 


13.  Thrust  right  hand  out  at  side 
once,  left  hand  once;  clap  hands  six 
times. 

14.  Thrust  right  hand  up,  left 
hand;  clap  hands  six  times. 

15.  Thrust  right  hand  forward, 
left  hand;  clap  hands  six  times. 

16.  On   one,  rise   on  toes.      On 
two,  bend  the  knees,  thus  sinking 
four  to  six  inches.     On  three,  rise; 
and,  on  four,  lower  heels  to  the 
floor.     Repeat  three  times. 

17.  First  position.    Thrust  right 
hand    down,    then    up.      Repeat. 
Thrust  left  hand  down,  then  up. 


Fig.  13. 


284 


GYMNASTICS. 


Repeat.  Alternate;  that  is,  thrust  right 
hand  down  and  left  hand  up  simulta- 
neously, Figure  14,  and  reverse.  Re- 
peat. Thrust  both  hands  down,  then 
both  hands  up.  Repeat.  This,  it  will 
be  noticed,  is  a  combination  of  the  first 
and  third  exercises  of  the  first  series. 


Fig.  14. 

18.  In  the  same  way  combine  the 
second  and  fourth  exercises  of  the 
first  series.  Figure  15.  At  close 
of  exercise  keep  the  hands  extended 
in  front  (Figure  3). 


GYMNASTICS. 


285 


19.  Double  time.     Spring 
forward  with  right  foot,  at 
the  same  time  carrying  both 
both  hands  as  far 
backwards  as  pos- 
sible in  a  horizontal   line, 
keeping    the    elbows    stiff. 
Figure  16.    Bring  the  right 
foot  back  to  position,  at  the 
same  time  carrying  the  arms 
back  to  the  position  indi- 
cated in  Figure  3.     Repeat 
three  times. 

20.  Same  with  left  foot. 


Fig.  16. 

THIRD  SERIES. 

1.  Fourth  position.  Figure  17. 
Thrust  right  hand  down  four  times, 
left  hand  four  times,  alternately 
four  times,  both  together  four  times. 


Fig.  17 


286 


GYMNASTICS. 


2.  Same  position.     Thrust  hands  out  at  side  in  same 
order.     Keep  arms  extended  at  last  movement. 

3.  Cross  the  arms  vigorously  over  the  chest  eight  times, 
right  and  left  arms  being  alternately  above,  as  teamsters 
do  to  warm  themselves. 

4.  Second  position.     Raise  the  toes  and  then  lower  to 
the  floor.     Eight  times. 


5.  Look  over  the  right  shoulder 
toward  the  feet  of  your  left  neighbor, 
then  over  the  left  shoulder  toward 
the  feet  of  your  right  neighbor,  alter- 
nately eight  times.  Figure  18. 
Double  time.  In  this  exercise  the 
body  may  be  twisted,  but  the  feet 
must  not  be  moved. 


Fig.  18. 

6.  Arms  hanging  at  the  side.  Wrist  exercise.  The 
hands  being  firmly  closed  and  the  palms  toward  the 
body,  bend  the  right  hand  outward  and  then  inward  as 
far  as  possible  four  times,  left  hand  four  times,  alternately 
four  times,  both  together  four  times.  If  preferred,  this 
exercise  and  the  three  following  may  each  be  simplified 
by  omitting  all  but  the  simultaneous  movement  of  the 
wrists,  performing  that  movement  in  each  case  eight  times. 


GYMNASTICS. 


287 


7.  Arms  horizontal  at  sides, 
palms  of  the  hands  downward, 
bend  the  hands 

upward          and 
downward  in  or- 
der of  preceding  exercise.  Fig- 
ures 19  and  20. 

8.  Hands  over  head,  palms 
facing  each  other,  bend  hands 
forward  and  backward  in  same 
order.    This  is  a  different  wrist 
movement  from  the  preceding. 

9.  Hands   directly  in   front, 
palms  facing,  bend  hands  up- 
ward and  downward.     Let  the 
hands  fall  at  the  side. 


Fig.  19. 


Fig.  20. 


10.  Combine  last  exercise  of 

first     series    with 
charges  (springing 
steps)     diagonally 
forward  four  times  to  right  and 
four  to  left.   Double  time.  Raise 
the    arms    while    taking    the 
springing  step,  and  lower  them 
while  returning  to  position. 

11.  Arms  hanging   at  sides. 
Common  time.    Twist  the  arms 
inward  four  times.     Raise  the 
arms  so  that  they  are  horizontal 
at  the  sides;  twist  four  times. 

12.  Hands  up  and  arms  ver- 
tical.    Twist  arms  four  times. 


288 


GYMNASTICS. 


Arms  extended  horizontally  in  front; 
twist  four  times.  Keep  the  arms  ex- 
tended in  readiness  for  next  exercise. 

13.  Elbow  exercise.  Bend  right  fore- 
arm on  upper  arm  four  times,  left  arm 
four  times,  right  and  left  alternately 
four  times, and  both  together  four  times. 

14.  Bring  the  arms  forcibly  back  to 
the  chest  eight  times,  thrusting  the 
shoulders  back.    Figures  3  and  21 
show  the  two  positions  of  this  move- 
ment. 


Fig.  22. 


Fig.  21. 

15.  First  position.    Thrust  right 
hand  to  right,  Figure  2,  and  re- 
cover position.    Thrust  right  hand 
to  left,  Figure  22,   and  recover 
position.      Perform    these    move- 
ments alternately  four  times.     In 
the  same  manner,  thrust  left  hand 
to  left,  then  to  right,  alternately 
four  times.     In  the  same  manner 
both  to  right,  then  to  left,  alter- 
nately four  times.      The  body  is 
turned  successively  to  right  and  to 
left  as  required  by  the  movement, 
but  the  feet  are  kept  firmly  fixed. 

16.  Arms  hanging  at  sides,  hands 


GYMNASTICS. 


289 


not  closed.  In  this  exercise  the  elbows  are  kept  unbent 
as  much  as  possible.  On  the  first  accented  beat,  clap 
the  hands  in  front;  on  the  unac- 
cented beat,  clap  them  behind  the 
body.  Repeat  three  times.  Clap 
the  hands  over  the  head,  then  back 
of  the  body.  Repeat  three  times. 
Alternate  these  movements  through 
a  strain. 

17.  Hands  clasped  behind  the 
head.  Head  held  well  back.  Fig- 
ure 23.  Bend  the  body  to  right 
and  left  alternately  eight  times. 
Double  time. 


Fig.  24. 


Fig.  23. 

18.  Same  position.    Bend  forward,  to 
the  right,  backward,  to  the  left,  recover- 
ing position  after  each  movement.    Re- 
peat in  reverse  order. 

19.  Extend    right    arm    diagonally 
forward,  curl  left  arm  over  the  head, 
and    spring    diagonally   forward   with 
right  foot.     Recover  position  on  second 
accented  beat,  at  the  same  time  letting 
the  arms  fall  downward.     Figure  24. 
Repeat  three  times. 


290 


GYMNASTICS. 


20.  Same  with  left  foot,  position 
of  arms  being  altered  accordingly. 
Figure  25. 


MARCHING. 

Calisthenic  practice  is  agreeably 
and  profitably  diversified  by  march- 
ing. To  secure  good  marching,  the 
pupil  must  observe  the  following 
directions: 

1.  Stand  exactly  opposite  the  seat 
from  which  you  have  risen,  until  the 
instant  comes  for  your  line  to  move. 
Fis-  %>•  2.  Beat  time  lightly  before  begin- 

ning to  march,  bringing  the  left  foot  to  the  floor  at  each 
accented  beat  of  the  music. 

3.  Keep  the  distance  uniform  between  yourself  and  the 
one  just  in  front  of  you. 

4.  Begin  to  march  with  the  left  foot. 

For  marching,  the  feet  may  be  placed  at  a  sharper  angle 
than  sixty  degrees.  Indeed,  the  angle  at  present  desig- 
nated in  military  tactics  is  twenty-two  and  a  half  degrees. 
The  body  is  to  be  held  erect,  with  shoulders  and  hips  drawn 
back.  The  knee  is  to  be  bent  but  slightly  in  marching, 
the  foot  being  carried  forward  in  such  a  way  that  the  ball 
of  the  foot  and  the  heel  strike  the  floor  at  exactly  the 
same  time.  This  will  determine  the  proper  length  of  the 
step,  which  for  an  adult  is  twenty-eight  inches  from  heel 
to  heel;  for  children  it  will,  of  course,  be  less.  Due 


GYMNASTICS.  291 

attention  to  this  method  of  stepping  will  develop  an  easy 
and  almost  noiseless  movement. 

As  the  greater  part  of  the  exercises  in  the  first  three 
series  are  for  the  upper  part  of  the  body,  a  fourth  series 
is  added,  which  consists  principally  of  movements  for  the 
feet.  It  is  made  up  of  beating  time,  facing,  marching, 
and  charges,  combined  with  arm  movements.  The  music 
of  "Hail  Columbia"  will  be  found  to  fit  the  series,  the 
melody  to  be  repeated  three  times. 

FOURTH  SERIES.  •  _ 

1.  Hands  on  shoulders.     Figure  9.     Spring  diagonally 
forward  to  the  right  with  the  right  foot,  at  the  same  time 
bringing  the  arms  upward  to  a  vertical  position.    On  two, 
recover  position.     Two  times.     Twice  with  left  foot. 

2.  Same  movement  of  arms,  the  charge  to  be  made 
diagonally  backward  with  right  foot.    Twice.    Same  with 
left  foot.     Drop  hands  at  side. 

3.  On  the  first  beat,  lift  the  right  foot  slightly  from  the 
floor,  and  turn  half  round  on  left  heel  used  as  a  pivot,  so 
as  to  face  the  right.      On  three,  turn  to  the  left,  thus 
facing  to  the  front  again.     On  five,  turn  to  left;  on  seven, 
to  the  right,  to  original  position. 

4.  Raise  the  right  foot,  carrying  it  a  short  space  diag- 
onally forward  to  the  right,  and  bring  the  toes  to  the 
floor.    Recover  position.    Four  times.   Left  foot  four  times. 

5.  Beat  time  during  four  beats,  lifting  each  foot  and 
bringing  to  floor  without  forward  motion.    Begin  with  left 
foot.     Then  take  eight  steps  forward,  the  eighth  being 
merely  to  place  the  right  foot  in  position  beside  the  left. 

6.  Beat  time  during  four  beats.     On  five,  turn  to  right 
as  in  Exercise  3;  on  seven,  to  right  again,  so  as  to  face 
the  back  of  the  room. 

19— P 


292  GYMNASTICS. 

7.  Take  eight  steps.     Turn  twice  as  in  last  half  of  pre- 
ceding exercise.    This  brings  the  pupil  to  his  first  position. 

8.  Simultaneously  raise  the  right  arm  to  a  horizontal 
position  at  the  side,  and  the  left  arm  to  a  horizontal  posi- 
tion in  front.     Four  times.     Change,  raising  right  arm 
in  front  and  left  at  the  side.     Four  times. 

9.  Double  time.     Spring  with  right  foot  to  the  right,  at 
the  same  time  extending  the  right  arm  horizontally  at  the 
side,  and  curling  the  left  arm  over  the  head.    Four  times. 

10.  Same  with  left  foot,  position  of  arms  being  altered 
accordingly. 

11.  Beat  time,  beginning  with  left  foot. 

12.  Turn  to  the  right,  as  in  Exercise  3;  two  beats. 
Eight  steps  sidewise  to  the  left.     Turn  to  the  left. 

1 3.  Draw  right  hand  up  under  armpit  twice,  left  twice, 
alternately  twice,  together  twice. 

14.  Half  face,  as  in  Exercise  12;  eight  steps  sidewise 
to  the  right;  half  face.     This,  it  will  be  observed,  brings 
the  pupil  back  to  original  position. 

15.  First  position.      Step  backward  with  right  foot,  at 
the  same  time  thrusting  the  hands  out  horizontally  at 
sides.     Recover  position.     Four  times. 

16.  Same  with  left  foot. 

17.  Beat  time. 

18.  Eight  steps  forward.     On  five,  place  right  foot  back 
of  left  at  right  angles  to  line  from  front  to  back  of  room, 


GYMNASTICS. 


293 


Fig.  26. 


the  heels  being  two  or  three  inches 
apart.  Figure  26.  At  six,  turn 
on  left  heel  so  as  to  face  the  back 
of  the  room.  This  movement 
should  always  be  made  to  the 
right.  Rest  during  two  beats. 

19.  Eight  steps  back  to  place. 
About  face,  as  in  preceding  exer- 
cise.    Rest  during  two  beats. 

20.  Double    time.       Springing 
steps  forward  to  the  left  with  right 
foot,  alternating  with  steps  to  the 
right  with  left  foot.     Touch  the 
tips  of  the  fingers  lightly  over- 
head at  each  step,  and  drop  the 
hands  at  the  side  while  recovering 
position.     Four  steps  with  right 
foot,  and  four  with  left. 


GOOD  BOOKS   OF  REFERENCE. 


GRAY'S  ANATOMY,  Descriptive  and  Surgical. 

MARTIN'S  HUMAN  BODY. 

MARTIN'S  HUMAN  BODY,  Briefer  Course. 

LEO'S  MANUAL  OF  PHYSIOLOGY. 

KIRKE'S  HAND-BOOK  OF  PHYSIOLOGY. 


,SITY  OP  CALIFORNIA  LIBRARY 

— ' • — 

t?OOK  IS  DUE  OT 


I  LJ     OOM  Awl 


